diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index 38fb46f..347ff68 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -283,18 +283,54 @@ async fn test_deno(app_handle: tauri::AppHandle) -> Result<String, String> {
     }
 }
 
+fn is_safe_path(path: &std::path::Path) -> bool {
+    !path.components().any(|c| matches!(c, std::path::Component::ParentDir))
+}
+
 #[tauri::command]
 async fn open_file(app: tauri::AppHandle, path: String) -> Result<(), String> {
     println!("open_file called for path: {}", path);
     use tauri_plugin_opener::OpenerExt;
-    app.opener().open_path(&path, None::<String>).map_err(|e| format!("Failed to open file: {}", e))
+    
+    let mut resolved_dest = std::path::PathBuf::from(&path);
+    if path.starts_with("~/") {
+        if let Ok(home) = app.path().home_dir() {
+            resolved_dest = home.join(&path[2..]);
+        }
+    } else if path == "~" {
+        if let Ok(home) = app.path().home_dir() {
+            resolved_dest = home;
+        }
+    }
+    
+    if !is_safe_path(&resolved_dest) {
+        return Err("Path traversal blocked".to_string());
+    }
+
+    app.opener().open_path(resolved_dest.to_string_lossy().as_ref(), None::<String>).map_err(|e| format!("Failed to open file: {}", e))
 }
 
 #[tauri::command]
 async fn show_in_folder(app: tauri::AppHandle, path: String) -> Result<(), String> {
     println!("show_in_folder called for path: {}", path);
     use tauri_plugin_opener::OpenerExt;
-    app.opener().reveal_item_in_dir(&path).map_err(|e| format!("Failed to reveal in folder: {}", e))
+    
+    let mut resolved_dest = std::path::PathBuf::from(&path);
+    if path.starts_with("~/") {
+        if let Ok(home) = app.path().home_dir() {
+            resolved_dest = home.join(&path[2..]);
+        }
+    } else if path == "~" {
+        if let Ok(home) = app.path().home_dir() {
+            resolved_dest = home;
+        }
+    }
+    
+    if !is_safe_path(&resolved_dest) {
+        return Err("Path traversal blocked".to_string());
+    }
+
+    app.opener().reveal_item_in_dir(resolved_dest.to_string_lossy().as_ref()).map_err(|e| format!("Failed to reveal in folder: {}", e))
 }
 
 use std::sync::atomic::{AtomicBool, Ordering};
@@ -538,8 +574,54 @@ async fn start_download(
             resolved_dest = home;
         }
     }
-    let _ = connections;
-    let _ = checksum;
+    
+    if !is_safe_path(&resolved_dest) {
+        return Err(AppError::Internal("Path traversal blocked".to_string()));
+    }
+
+    if connections.unwrap_or(1) > 1 || checksum.is_some() {
+        println!("Routing multi-part/checksum download to aria2: {}", id);
+        let mut options = serde_json::Map::new();
+        options.insert("dir".to_string(), serde_json::json!(resolved_dest.to_string_lossy().to_string()));
+        options.insert("out".to_string(), serde_json::json!(filename));
+        if let Some(conn) = connections {
+            options.insert("split".to_string(), serde_json::json!(conn.to_string()));
+            options.insert("max-connection-per-server".to_string(), serde_json::json!(conn.to_string()));
+        }
+        if let Some(speed) = speed_limit {
+            options.insert("max-download-limit".to_string(), serde_json::json!(speed));
+        }
+        if let Some(user) = username {
+            options.insert("http-user".to_string(), serde_json::json!(user));
+        }
+        if let Some(pass) = password {
+            options.insert("http-passwd".to_string(), serde_json::json!(pass));
+        }
+        if let Some(chk) = checksum {
+            options.insert("checksum".to_string(), serde_json::json!(chk));
+        }
+        if let Some(ua) = user_agent {
+            options.insert("user-agent".to_string(), serde_json::json!(ua));
+        }
+        if let Some(prox) = proxy {
+            options.insert("all-proxy".to_string(), serde_json::json!(prox));
+        }
+        if let Some(cook) = cookies {
+            options.insert("header".to_string(), serde_json::json!(format!("Cookie: {}", cook)));
+        }
+        
+        let params = serde_json::json!([
+            [url],
+            options
+        ]);
+        
+        rpc_call(state.aria2_port, &state.aria2_secret, "aria2.addUri", params)
+            .await
+            .map(|_| ())
+            .map_err(|e| AppError::Internal(e))?;
+            
+        return Ok(());
+    }
     state
         .download_coordinator
         .send(download::DownloadCmd::Start(download::DownloadPayload {
@@ -927,25 +1009,29 @@ fn perform_system_action(action: crate::ipc::PostQueueAction) -> Result<(), Stri
 
 #[tauri::command]
 async fn set_concurrent_limit(state: tauri::State<'_, AppState>, limit: usize) -> Result<(), String> {
-    let _ = rpc_call(
+    rpc_call(
         state.aria2_port,
         &state.aria2_secret,
         "aria2.changeGlobalOption",
         serde_json::json!([{"max-concurrent-downloads": limit.to_string()}])
-    ).await;
-    Ok(())
+    ).await.map(|_| ()).map_err(|e| {
+        eprintln!("Failed to set concurrent limit: {}", e);
+        e
+    })
 }
 
 #[tauri::command]
 async fn set_global_speed_limit(state: tauri::State<'_, AppState>, limit: Option<String>) -> Result<(), String> {
     let limit_str = limit.unwrap_or_else(|| "0".to_string());
-    let _ = rpc_call(
+    rpc_call(
         state.aria2_port,
         &state.aria2_secret,
         "aria2.changeGlobalOption",
         serde_json::json!([{"max-overall-download-limit": limit_str}])
-    ).await;
-    Ok(())
+    ).await.map(|_| ()).map_err(|e| {
+        eprintln!("Failed to set global speed limit: {}", e);
+        e
+    })
 }
 
 #[tauri::command]
@@ -957,16 +1043,18 @@ fn request_automation_permission() -> Result<(), String> {
         use objc::{msg_send, sel, sel_impl, class};
 
         unsafe {
-            let script_str = NSString::alloc(nil).init_str("tell application \"Finder\" to get name");
-            let ns_apple_script: id = msg_send![class!(NSAppleScript), alloc];
-            let ns_apple_script: id = msg_send![ns_apple_script, initWithSource: script_str];
-            let mut error_dict: id = nil;
-            let result: id = msg_send![ns_apple_script, executeAndReturnError: &mut error_dict];
-            if result == nil {
-                return Err("Automation permission was not granted".to_string());
-            }
+            objc::rc::autoreleasepool(|| {
+                let script_str = NSString::alloc(nil).init_str("tell application \"Finder\" to get name");
+                let ns_apple_script: id = msg_send![class!(NSAppleScript), alloc];
+                let ns_apple_script: id = msg_send![ns_apple_script, initWithSource: script_str];
+                let mut error_dict: id = nil;
+                let result: id = msg_send![ns_apple_script, executeAndReturnError: &mut error_dict];
+                if result == nil {
+                    return Err("Automation permission was not granted".to_string());
+                }
+                Ok(())
+            })
         }
-        return Ok(());
     }
 
     #[cfg(not(target_os = "macos"))]
@@ -1067,6 +1155,9 @@ fn check_file_exists(app_handle: tauri::AppHandle, path: String) -> bool {
             resolved_dest = home;
         }
     }
+    if !is_safe_path(&resolved_dest) {
+        return false;
+    }
     resolved_dest.exists()
 }
 
@@ -1083,6 +1174,9 @@ fn delete_file(app_handle: tauri::AppHandle, path: String) -> Result<(), String>
             resolved_dest = home;
         }
     }
+    if !is_safe_path(&resolved_dest) {
+        return Err("Path traversal blocked".to_string());
+    }
     if resolved_dest.exists() {
         std::fs::remove_file(resolved_dest).map_err(|e| e.to_string())
     } else {
diff --git a/src-tauri/src/parity.rs b/src-tauri/src/parity.rs
index e469ac5..29f91df 100644
--- a/src-tauri/src/parity.rs
+++ b/src-tauri/src/parity.rs
@@ -8,9 +8,8 @@ pub async fn get_system_proxy() -> Result<Option<String>, String> {
     match sysproxy::Sysproxy::get_system_proxy() {
         Ok(proxy) => {
             if proxy.enable {
-                // Determine protocol, usually sysproxy returns the host and port
-                // We'll default to http:// unless the user has configured something specific
-                Ok(Some(format!("http://{}:{}", proxy.host, proxy.port)))
+                let protocol = if proxy.host.contains("://") { "" } else { "http://" };
+                Ok(Some(format!("{}{}:{}", protocol, proxy.host, proxy.port)))
             } else {
                 Ok(None)
             }
diff --git a/src/components/AddDownloadsModal.tsx b/src/components/AddDownloadsModal.tsx
index b568569..a07e6ed 100644
--- a/src/components/AddDownloadsModal.tsx
+++ b/src/components/AddDownloadsModal.tsx
@@ -317,6 +317,7 @@ export const AddDownloadsModal = () => {
 
   // Metadata parser
   useEffect(() => {
+    let active = true;
     const lines = urls.split('\n').map(u => u.trim()).filter(u => u.length > 0);
 
     // Immediately display items in loading state
@@ -340,6 +341,7 @@ export const AddDownloadsModal = () => {
       let firstReadyIndex: number | null = null;
 
       for (let i = 0; i < lines.length; i++) {
+        if (!active) break;
         const url = lines[i];
         try {
           new URL(url);
@@ -408,15 +410,18 @@ export const AddDownloadsModal = () => {
           console.error("Meta fetch failed", e);
           updatedItems[i] = { ...updatedItems[i], size: 'Unknown', sizeBytes: 0, status: 'Error' };
         }
-        setParsedItems([...updatedItems]);
+        if (active) setParsedItems([...updatedItems]);
       }
 
-      if (firstReadyIndex !== null) {
+      if (active && firstReadyIndex !== null) {
         setSelectedItemIndex(firstReadyIndex);
       }
     }, 400);
 
-    return () => clearTimeout(timer);
+    return () => {
+      active = false;
+      clearTimeout(timer);
+    };
   }, [urls, pendingAddFilename]);
 
   if (!isAddModalOpen) return null;
diff --git a/src/components/SettingsView.tsx b/src/components/SettingsView.tsx
index 46c094e..c3d9ae8 100644
--- a/src/components/SettingsView.tsx
+++ b/src/components/SettingsView.tsx
@@ -245,6 +245,11 @@ export default function SettingsView() {
                     type="number" min="1" max="16"
                     value={settings.perServerConnections}
                     onChange={(e) => settings.setPerServerConnections(Number(e.target.value))}
+                    onBlur={(e) => {
+                      const val = Number(e.target.value);
+                      if (val < 1) settings.setPerServerConnections(1);
+                      if (val > 16) settings.setPerServerConnections(16);
+                    }}
                     className="app-control w-24 text-center"
                   />
                 </div>
@@ -257,6 +262,11 @@ export default function SettingsView() {
                     type="number" min="1" max="12"
                     value={settings.maxConcurrentDownloads}
                     onChange={(e) => settings.setMaxConcurrentDownloads(Number(e.target.value))}
+                    onBlur={(e) => {
+                      const val = Number(e.target.value);
+                      if (val < 1) settings.setMaxConcurrentDownloads(1);
+                      if (val > 12) settings.setMaxConcurrentDownloads(12);
+                    }}
                     className="app-control w-24 text-center"
                   />
                 </div>
@@ -285,6 +295,11 @@ export default function SettingsView() {
                     type="number" min="0" max="10"
                     value={settings.maxAutomaticRetries}
                     onChange={(e) => settings.setMaxAutomaticRetries(Number(e.target.value))}
+                    onBlur={(e) => {
+                      const val = Number(e.target.value);
+                      if (val < 0) settings.setMaxAutomaticRetries(0);
+                      if (val > 10) settings.setMaxAutomaticRetries(10);
+                    }}
                     className="app-control w-24 text-center"
                   />
                 </div>
@@ -453,9 +468,14 @@ export default function SettingsView() {
                     <div className="mac-settings-row">
                       <span className="text-[13px] text-text-primary pl-4">Proxy Port</span>
                       <input
-                        type="number"
+                        type="number" min="1" max="65535"
                         value={settings.proxyPort}
                         onChange={(e) => settings.setProxyPort(Number(e.target.value))}
+                        onBlur={(e) => {
+                          const val = Number(e.target.value);
+                          if (val < 1) settings.setProxyPort(1);
+                          if (val > 65535) settings.setProxyPort(65535);
+                        }}
                         className="app-control w-24 text-center"
                       />
                     </div>
diff --git a/src/store/useDownloadStore.ts b/src/store/useDownloadStore.ts
index 4a0f762..1328a20 100644
--- a/src/store/useDownloadStore.ts
+++ b/src/store/useDownloadStore.ts
@@ -9,6 +9,7 @@ import { useSettingsStore } from './useSettingsStore';
 export type { DownloadCategory } from '../utils/downloads';
 
 const getProxyArgs = (settings: ReturnType<typeof useSettingsStore.getState>) => {
+  if (settings.proxyMode === 'system') return 'system';
   if (settings.proxyMode === 'custom' && settings.proxyHost) {
     return `http://${settings.proxyHost}:${settings.proxyPort}`;
   }
@@ -25,7 +26,8 @@ export const getSiteLogin = (url: string, settings: ReturnType<typeof useSetting
         const suffix = pattern.substring(2);
         if (host === suffix || host.endsWith('.' + suffix)) return login;
       } else if (pattern.includes('*')) {
-        const regex = new RegExp('^' + pattern.replace(/\*/g, '.*') + '$');
+        const escaped = pattern.replace(/[.+?^${}()|[\]\\]/g, '\\$&');
+        const regex = new RegExp('^' + escaped.replace(/\*/g, '.*') + '$');
         if (regex.test(host)) return login;
       } else if (host === pattern) {
         return login;
@@ -191,9 +193,13 @@ export const useDownloadStore = create<DownloadState>((set, get) => ({
   },
   redownload: (id) => {
     let updatedItem: DownloadItem | null = null;
+    let wasDownloading = false;
     set((state) => ({
       downloads: state.downloads.map(d => {
         if (d.id === id) {
+          if (d.status === 'downloading') {
+            wasDownloading = true;
+          }
           const updated: DownloadItem = { ...d, status: 'queued', _dispatched: false, fraction: 0, speed: '-', eta: '-' };
           updatedItem = updated;
           return updated;
@@ -201,6 +207,9 @@ export const useDownloadStore = create<DownloadState>((set, get) => ({
         return d;
       })
     }));
+    if (wasDownloading) {
+      invoke('pause_download', { id }).catch(console.error);
+    }
     if (updatedItem) {
       const toSave = { ...(updatedItem as DownloadItem) };
       delete toSave.fraction; delete toSave.speed; delete toSave.eta;
diff --git a/src/utils/downloads.ts b/src/utils/downloads.ts
index a38308c..4626667 100644
--- a/src/utils/downloads.ts
+++ b/src/utils/downloads.ts
@@ -11,8 +11,10 @@ const MEDIA_DOMAINS = [
   'instagram.com',
   'tiktok.com',
   'reddit.com',
+  'v.redd.it',
   'soundcloud.com',
-  'facebook.com'
+  'facebook.com',
+  'fb.watch'
 ];
 
 export const categoryForFileName = (fileName: string): DownloadCategory => {