diff --git a/Cad/TemplateDrawingService.cs b/Cad/TemplateDrawingService.cs
index 2e2b629..ce00fec 100644
--- a/Cad/TemplateDrawingService.cs
+++ b/Cad/TemplateDrawingService.cs
@@ -36,11 +36,26 @@ namespace CadParamPluging.Cad
             "尺寸标注", "标注", "DIM", "DIMENSION", "DIMENSIONS"
         };
 
-        public static Document CreateDocumentFromTemplate(TemplateInfo template)
+        public static Document OpenTemplateDrawing(TemplateInfo template)
         {
-            var doc = Application.DocumentManager.Add(template.FilePath);
-            Application.DocumentManager.MdiActiveDocument = doc;
-            return doc;
+            if (template == null || string.IsNullOrWhiteSpace(template.FilePath))
+            {
+                throw new ArgumentException("Template path is invalid");
+            }
+
+            var docMgr = Application.DocumentManager;
+            foreach (Document doc in docMgr)
+            {
+                if (string.Equals(doc.Name, template.FilePath, StringComparison.OrdinalIgnoreCase))
+                {
+                    docMgr.MdiActiveDocument = doc;
+                    return doc;
+                }
+            }
+
+            var newDoc = docMgr.Open(template.FilePath, false);
+            docMgr.MdiActiveDocument = newDoc;
+            return newDoc;
         }
 
         /// <summary>
@@ -859,6 +874,7 @@ namespace CadParamPluging.Cad
             public int OuterFrameErased { get; set; }
             public Point3d OriginalCenter { get; set; }
             public Extents3d? OriginalExtents { get; set; }
+            public Extents3d? WhiteFrameExtents { get; set; }
         }
 
         private static readonly Regex DimensionPlaceholderRegex = new Regex(
@@ -892,6 +908,9 @@ namespace CadParamPluging.Cad
 
             var layoutExtents = ComputeLayoutExtents(allEntities);
             var caxaExtents = ComputeCaxaLayerExtents(tr, allEntities);
+            // Calculate white frame extents
+            var whiteFrameExtents = ComputeWhiteFrameExtentsFromEntities(tr, allEntities) ?? ComputeLayoutExtents(allEntities);
+            result.WhiteFrameExtents = whiteFrameExtents;
 
             if (caxaExtents.HasValue)
             {
@@ -901,6 +920,17 @@ namespace CadParamPluging.Cad
                     (caxaExtents.Value.MinPoint.Y + caxaExtents.Value.MaxPoint.Y) / 2,
                     0);
             }
+            else if (whiteFrameExtents.HasValue)
+            {
+                // Fallback to center of the upper half of the white frame if no CAXA layer found
+                var frame = whiteFrameExtents.Value;
+                var centerX = (frame.MinPoint.X + frame.MaxPoint.X) / 2.0;
+                var height = frame.MaxPoint.Y - frame.MinPoint.Y;
+                // Default to 70% height (center of upper area approximately) or just center?
+                // User said "upper half center". Top half is [0.5, 1.0], center is 0.75.
+                var centerY = frame.MinPoint.Y + height * 0.75; 
+                result.OriginalCenter = new Point3d(centerX, centerY, 0);
+            }
 
             // 使用CAXA图层范围作为图形区域，用于判断右上角
             var graphicExtents = caxaExtents ?? layoutExtents;
diff --git a/UI/ParamDrawingPanel.cs b/UI/ParamDrawingPanel.cs
index 484be1c..63d0391 100644
--- a/UI/ParamDrawingPanel.cs
+++ b/UI/ParamDrawingPanel.cs
@@ -265,6 +265,17 @@ namespace CadParamPluging.UI
                             // Here we just list them.
                             items.Add(item);
                         }
+
+                        // Fallback: if no layouts/model candidates found, add the file as a generic "Model Space" entry
+                        if (layouts.Count == 0 && models.Count == 0)
+                        {
+                            items.Add(new TemplateSelectionItem(new TemplateInfo
+                            {
+                                Name = Path.GetFileName(cadPath),
+                                FilePath = cadPath,
+                                LayoutName = null // Default to Model space
+                            }));
+                        }
                     }
                     catch (Exception ex)
                     {
@@ -567,7 +578,7 @@ namespace CadParamPluging.UI
 
                 DomainFacade.ValidateParameters(tplParams, drawingParams);
 
-                var doc = TemplateDrawingService.CreateDocumentFromTemplate(_selectedTemplate);
+                var doc = TemplateDrawingService.OpenTemplateDrawing(_selectedTemplate);
 
                 if (_selectedModelWindow.HasValue)
                 {
@@ -624,7 +635,23 @@ namespace CadParamPluging.UI
                     }
 
                     var scaleFactor = ParseScaleFactor(bag.GetString("DrawingScale"));
-
+                    
+                    if (removeResult.WhiteFrameExtents.HasValue && removeResult.CaxaLayerErased == 0)
+                    {
+                         AppendLog($"未检测到CAXA层，已切换至白框定位: {removeResult.OriginalCenter}");
+                    }
+                    else
+                    {
+                         AppendLog($"原图中心点: {removeResult.OriginalCenter}");
+                    }
+                    AppendLog($"绘图参数: Type={tplParams.ProjectType}, Size={tplParams.SheetSize}, Scale={tplParams.Scale}, Method={tplParams.DrawingType}");
+                    
+                    // Dubug: Dump bag keys
+                    var bagKeys = bag.GetKeys(); // Assuming GetKeys exists? If not, skip or use reflection?
+                    // ParamBag implementation is simple dictionary usually.
+                    // Let's just log specific keys we suspect.
+                    AppendLog($"Bag Keys check: OD1={bag.GetDoubleOrNull("OuterDiameter1")}, H1={bag.GetDoubleOrNull("Height1")}");
+                    
                     // 根据模板参数绘制半剖视图，居中放置于原图纸位置
                     // 使用特征驱动模式：根据参数存在性动态绘制对应特征
                     HalfSectionDrawer.Draw(
@@ -637,6 +664,9 @@ namespace CadParamPluging.UI
                         removeResult.OriginalCenter,  // 原图纸中心点
                         scaleFactor  // 缩放比例
                     );
+                    
+                    // Force Zoom Extents to ensure visibility
+                    try { doc.SendStringToExecute("._ZOOM _E ", true, false, false); } catch { }
 
                     // 更新标题栏中的比例属性
                     var scaleUpdated = TemplateDrawingService.UpdateScaleAttribute(