diff --git a/src/c#/GeneralUpdate.Core/Download/DownloadPlanBuilder.cs b/src/c#/GeneralUpdate.Core/Download/DownloadPlanBuilder.cs
index 038d0e4e..37c11abd 100644
--- a/src/c#/GeneralUpdate.Core/Download/DownloadPlanBuilder.cs
+++ b/src/c#/GeneralUpdate.Core/Download/DownloadPlanBuilder.cs
@@ -22,6 +22,7 @@ public static class DownloadPlanBuilder
     public static DownloadPlan Build(IEnumerable<DownloadAsset> assets, string currentVersion)
     {
         if (assets == null) return DownloadPlan.Empty;
+        if (ParseVersion(currentVersion) == null) return DownloadPlan.Empty;
 
         // 1. Filter out frozen packages
         var active = assets
diff --git a/src/c#/GeneralUpdate.Core/Download/MultiEventArgs/UpdateInfoEventArgs.cs b/src/c#/GeneralUpdate.Core/Download/MultiEventArgs/UpdateInfoEventArgs.cs
index b0dfef83..89db4e3b 100644
--- a/src/c#/GeneralUpdate.Core/Download/MultiEventArgs/UpdateInfoEventArgs.cs
+++ b/src/c#/GeneralUpdate.Core/Download/MultiEventArgs/UpdateInfoEventArgs.cs
@@ -3,7 +3,7 @@
 
 namespace GeneralUpdate.Core.Download;
 
-public class UpdateInfoEventArgs(VersionRespDTO info) : EventArgs
+public class UpdateInfoEventArgs(VersionRespDTO? info = null) : EventArgs
 {
-    public VersionRespDTO Info { get; private set; } = info;
+    public VersionRespDTO? Info { get; private set; } = info;
 }
diff --git a/src/c#/GeneralUpdate.Core/Download/Orchestrators/DefaultDownloadOrchestrator.cs b/src/c#/GeneralUpdate.Core/Download/Orchestrators/DefaultDownloadOrchestrator.cs
index d398109e..1e1fcb6f 100644
--- a/src/c#/GeneralUpdate.Core/Download/Orchestrators/DefaultDownloadOrchestrator.cs
+++ b/src/c#/GeneralUpdate.Core/Download/Orchestrators/DefaultDownloadOrchestrator.cs
@@ -40,9 +40,11 @@ public async Task<DownloadReport> ExecuteAsync(
         if (plan == null || !plan.HasAssets)
             return new DownloadReport(Array.Empty<DownloadResult>(), 0, TimeSpan.Zero, 0, 0);
 
+        Directory.CreateDirectory(destDir);
+
         var sw = Stopwatch.StartNew();
         var results = new List<DownloadResult>();
-        var sem = new SemaphoreSlim(maxConcurrency);
+        using var sem = new SemaphoreSlim(maxConcurrency);
         long totalBytes = 0;
 
         var tasks = plan.Assets.Select(async asset =>
diff --git a/src/c#/GeneralUpdate.Core/Strategy/ClientUpdateStrategy.cs b/src/c#/GeneralUpdate.Core/Strategy/ClientUpdateStrategy.cs
index 79636488..8c31acd9 100644
--- a/src/c#/GeneralUpdate.Core/Strategy/ClientUpdateStrategy.cs
+++ b/src/c#/GeneralUpdate.Core/Strategy/ClientUpdateStrategy.cs
@@ -172,9 +172,19 @@ private async Task ExecuteStandardWorkflowAsync(Encoding encoding, int timeout)
         }
 
         // Build process info for the upgrade process
+        // Convert DownloadAsset list to VersionInfo for ProcessInfo compatibility
+        var downloadVersions = downloadPlan.Assets.Select(a => new VersionInfo
+        {
+            Name = a.Name,
+            Hash = a.SHA256,
+            Url = a.Url,
+            Version = a.Version,
+            Format = "ZIP"
+        }).ToList();
+
         _configInfo.ProcessInfo = JsonSerializer.Serialize(
             ConfigurationMapper.MapToProcessInfo(
-                _configInfo, new List<VersionInfo>(),
+                _configInfo, downloadVersions,
                 BlackListManager.Instance.BlackFormats.ToList(),
                 BlackListManager.Instance.BlackFiles.ToList(),
                 BlackListManager.Instance.SkipDirectorys.ToList()),
@@ -185,17 +195,21 @@ private async Task ExecuteStandardWorkflowAsync(Encoding encoding, int timeout)
 
         _osStrategy!.Create(_configInfo);
 
-        // Download via orchestrator (replaces old DownloadManager)
+        // Download via orchestrator
         GeneralTracer.Info($"ClientUpdateStrategy: downloading {downloadPlan.Assets.Count} asset(s).");
-        var httpClient = new System.Net.Http.HttpClient();
-        try
+        if (_orchestrator != null)
         {
-            var orchestrator = new Download.Orchestrators.DefaultDownloadOrchestrator(httpClient);
-            await orchestrator.ExecuteAsync(downloadPlan, _configInfo.TempPath).ConfigureAwait(false);
+            await _orchestrator.ExecuteAsync(downloadPlan, _configInfo.TempPath).ConfigureAwait(false);
         }
-        finally
+        else
         {
-            httpClient.Dispose();
+            var httpClient = new System.Net.Http.HttpClient();
+            try
+            {
+                var orchestrator = new Download.Orchestrators.DefaultDownloadOrchestrator(httpClient);
+                await orchestrator.ExecuteAsync(downloadPlan, _configInfo.TempPath).ConfigureAwait(false);
+            }
+            finally { httpClient.Dispose(); }
         }
 
         await SafeReportDownloadCompletedAsync(hooksCtx).ConfigureAwait(false);
diff --git a/src/c#/GeneralUpdate.Core/Strategy/OSSUpdateStrategy.cs b/src/c#/GeneralUpdate.Core/Strategy/OSSUpdateStrategy.cs
index b87c8cbd..34fd2cd6 100644
--- a/src/c#/GeneralUpdate.Core/Strategy/OSSUpdateStrategy.cs
+++ b/src/c#/GeneralUpdate.Core/Strategy/OSSUpdateStrategy.cs
@@ -117,17 +117,32 @@ public void StartApp()
 
     private async Task DownloadVersionsAsync(List<VersionOSS> versions)
     {
-        var assets = versions.Select(v => new Download.Models.DownloadAsset(
-            Name: v.PacketName ?? v.Version ?? "unknown",
-            Url: v.Url ?? string.Empty,
-            Size: 0,
-            SHA256: v.Hash,
-            Version: v.Version ?? "0.0.0"
-        )).ToList();
+        var assets = versions.Select(v =>
+        {
+            if (string.IsNullOrWhiteSpace(v.Url))
+                throw new InvalidOperationException(
+                    $"OSS version '{v.PacketName ?? v.Version}' has no download URL.");
+
+            // Use PacketName.zip as the filename to match Decompress() expectations.
+            // The orchestrator falls back to {Name}.{Version} when URL-based extraction fails,
+            // so we set Version to "zip" to produce e.g. "myapp.zip.zip".
+            // Better: set Name to the zip filename directly.
+            var zipName = $"{v.PacketName ?? v.Version}zip";
+            if (!zipName.EndsWith(".zip", StringComparison.OrdinalIgnoreCase))
+                zipName += ".zip";
+
+            return new Download.Models.DownloadAsset(
+                Name: zipName,
+                Url: v.Url,
+                Size: 0,
+                SHA256: v.Hash,
+                Version: v.Version ?? "0.0.0"
+            );
+        }).ToList();
 
         var plan = new Download.Models.DownloadPlan(assets, false);
 
-        var httpClient = new System.Net.Http.HttpClient();
+        var httpClient = new System.Net.Http.HttpClient { Timeout = TimeSpan.FromSeconds(TimeOut) };
         try
         {
             var orchestrator = new Download.Orchestrators.DefaultDownloadOrchestrator(httpClient);