Put the SortOrder in the AddIn-Tree; and remove the SortOrder.xml files.

data/templates/file/CSharp/FileCategorySortOrder.xml

@@ -1,5 +0,0 @@
-<Categories>
-	<Category Name="C#">
-		<Category Name="${res:Templates.File.Categories.WindowsApplications}" SortOrder="10"/>
-	</Category>
-</Categories>

data/templates/file/VB/FileCategorySortOrder.xml

@@ -1,5 +0,0 @@
-<Categories>
-	<Category Name="VB">
-		<Category Name="${res:Templates.File.Categories.WindowsApplications}" SortOrder="10"/>
-	</Category>
-</Categories>

data/templates/project/CSharp/ProjectCategorySortOrder.xml

@@ -1,5 +0,0 @@
-<Categories>
-	<Category Name="C#">
-		<Category Name="${res:Templates.File.Categories.WindowsApplications}" SortOrder="10"/>
-	</Category>
-</Categories>

data/templates/project/VB/ProjectCategorySortOrder.xml

@@ -1,5 +0,0 @@
-<Categories>
-	<Category Name="VB">
-		<Category Name="${res:Templates.File.Categories.WindowsApplications}" SortOrder="10"/>
-	</Category>
-</Categories>

src/AddIns/BackendBindings/CSharpBinding/Project/CSharpBinding.addin

@@ -62,6 +62,16 @@
 		<CodeCompletionBinding id = "CSharp" extensions = ".cs" class = "CSharpBinding.Completion.CSharpCompletionBinding"/>
 	</Path>
 	
+	<Path name = "/SharpDevelop/BackendBindings/Templates">
+		<!-- The contents of the template categories is provided by the data/templates folder
+			in which SharpDevelop looks by default. We explicitly list the category only in order to assign
+			the sortOrder.
+		-->
+		<TemplateCategory id = "C#">
+			<TemplateCategory id = "${res:Templates.File.Categories.WindowsApplications}" sortOrder="10" />
+		</TemplateCategory>
+	</Path>
+	
 	<Path name="/SharpDevelop/Workbench/LanguageBindings">
 		<LanguageBinding
 			id="CSharp"

src/Main/Base/Project/ICSharpCode.SharpDevelop.addin

@@ -49,6 +49,7 @@
 			<Doozer name="TaskBoundAdditionalLogger" class="ICSharpCode.SharpDevelop.Project.TaskBoundAdditionalLoggerDoozer"/>
 			<Doozer name="TaskBoundLoggerFilter" class="ICSharpCode.SharpDevelop.Project.TaskBoundLoggerFilterDoozer"/>
 			<Doozer name="TemplateFile" class="ICSharpCode.SharpDevelop.Templates.TemplateFileDoozer"/>
+			<Doozer name="TemplateCategory" class="ICSharpCode.SharpDevelop.Templates.TemplateCategoryDoozer"/>
 		</Import>
 		<Import assembly=":SharpDevelop">
 			<Doozer name="Parser" class="ICSharpCode.SharpDevelop.Parser.ParserDoozer"/>

src/Main/Base/Project/Src/Gui/Dialogs/NewFileDialog.cs

@@ -98,15 +98,22 @@ namespace ICSharpCode.SharpDevelop.Gui
 		
 		void InitializeTemplates(IEnumerable<TemplateCategory> templateCategories)
 		{
-			foreach (var templateCategory in templateCategories) {
-				categoryTreeView.Nodes.Add(CreateCategory(templateCategory));
+			foreach (var templateCategory in Sorted(templateCategories)) {
+				var cat = CreateCategory(templateCategory);
+				if (!cat.IsEmpty)
+					categoryTreeView.Nodes.Add(cat);
 			}
 		}
 		
+		IEnumerable<TemplateCategory> Sorted(IEnumerable<TemplateCategory> templateCategories)
+		{
+			return templateCategories.OrderByDescending(c => c.SortOrder).ThenBy(c => StringParser.Parse(c.DisplayName));
+		}
+		
 		Category CreateCategory(TemplateCategory templateCategory)
 		{
 			Category node = new NewFileDialog.Category(templateCategory.DisplayName);
-			foreach (var subcategory in templateCategory.Subcategories) {
+			foreach (var subcategory in Sorted(templateCategory.Subcategories)) {
 				var subnode = CreateCategory(subcategory);
 				if (!subnode.IsEmpty)
 					node.Nodes.Add(subnode);

src/Main/Base/Project/Src/Gui/Dialogs/NewProjectDialog.cs

@@ -89,17 +89,24 @@ namespace ICSharpCode.SharpDevelop.Project.Dialogs
 		}
 		
 		
+		IEnumerable<TemplateCategory> Sorted(IEnumerable<TemplateCategory> templateCategories)
+		{
+			return templateCategories.OrderByDescending(c => c.SortOrder).ThenBy(c => StringParser.Parse(c.DisplayName));
+		}
+		
 		protected virtual void InitializeTemplates(IEnumerable<TemplateCategory> templateCategories)
 		{
-			foreach (var templateCategory in templateCategories) {
-				categoryTreeView.Nodes.Add(CreateCategory(templateCategory));
+			foreach (var templateCategory in Sorted(templateCategories)) {
+				var cat = CreateCategory(templateCategory);
+				if (!cat.IsEmpty)
+					categoryTreeView.Nodes.Add(cat);
 			}
 		}
 		
 		Category CreateCategory(TemplateCategory templateCategory)
 		{
 			Category node = new Category(templateCategory.DisplayName);
-			foreach (var subcategory in templateCategory.Subcategories) {
+			foreach (var subcategory in Sorted(templateCategory.Subcategories)) {
 				var subnode = CreateCategory(subcategory);
 				if (!subnode.IsEmpty)
 					node.Nodes.Add(subnode);

src/Main/Base/Project/Templates/TemplateCategory.cs

@@ -16,6 +16,12 @@ namespace ICSharpCode.SharpDevelop.Templates
 		readonly string description;
 		readonly IImage icon;
 		
+		/// <summary>
+		/// An integer that is used for sorting; categories with higher values are listed first.
+		/// For equal values, the categories will be sorted by the display name.
+		/// </summary>
+		public int SortOrder { get; set; }
+		
 		public override string Name {
 			get { return name; }
 		}

src/Main/SharpDevelop/Templates/TemplateCategoryDoozer.cs

@@ -2,7 +2,9 @@
 // This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
 
 using System;
+using System.Collections.Generic;
 using ICSharpCode.Core;
+using ICSharpCode.NRefactory.Utils;
 
 namespace ICSharpCode.SharpDevelop.Templates
 {
@@ -12,6 +14,10 @@ namespace ICSharpCode.SharpDevelop.Templates
 	/// <attribute name="displayName" use="optional">
 	/// The display name to use. If not specified, the codon id is used instead.
 	/// </attribute>
+	/// <attribute name="sortOrder" use="optional">
+	/// An integer that is used for sorting; categories with higher values are listed first.
+	/// For equal values, the categories will be sorted by the display name.
+	/// </attribute>
 	/// <children childTypes="TemplateBase">
 	/// The &lt;TemplateCategory&gt; may have templates and subcategories as children.
 	/// </children>
@@ -31,18 +37,26 @@ namespace ICSharpCode.SharpDevelop.Templates
 			if (args.Codon.Properties.Contains("icon"))
 				icon = SD.ResourceService.GetImage(args.Codon.Properties["icon"]);
 			TemplateCategory category = new TemplateCategory(
-				args.Codon.Id, 
+				args.Codon.Id,
 				args.Codon.Properties["displayName"],
 				args.Codon.Properties["description"],
 				icon
 			);
+			int sortOrder;
+			if (int.TryParse(args.Codon.Properties["sortOrder"], out sortOrder))
+				category.SortOrder = sortOrder;
+			LoadSubItems(category, args);
+			return category;
+		}
+		
+		void LoadSubItems(TemplateCategory category, BuildItemArgs args)
+		{
 			foreach (TemplateBase item in args.BuildSubItems<TemplateBase>()) {
 				if (item is TemplateCategory)
 					category.Subcategories.Add((TemplateCategory)item);
 				else
 					category.Templates.Add(item);
 			}
-			return category;
 		}
 	}
 }

src/Main/SharpDevelop/Templates/TemplateService.cs

@@ -6,8 +6,8 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Xml;
-
 using ICSharpCode.Core;
+using ICSharpCode.NRefactory.Utils;
 
 namespace ICSharpCode.SharpDevelop.Templates
 {
@@ -38,14 +38,15 @@ namespace ICSharpCode.SharpDevelop.Templates
 		{
 			var items = SD.AddInTree.BuildItems<TemplateBase>(TemplatePath, this, false);
 			var categories = items.OfType<TemplateCategory>().ToList();
-			foreach (ICategory classicTemplate in items.Except(categories)) {
+			foreach (var classicTemplate in items.Except(categories)) {
 				// compatibility with the SD <=4.x way of adding templates:
 				// define category+subcategory in the .xft/.xpt file,
 				// and the category gets created automatically
-				var cat = GetOrCreateClassicCategory(categories, classicTemplate.Category);
-				if (!string.IsNullOrEmpty(classicTemplate.Subcategory))
-					cat = GetOrCreateClassicCategory(cat.Subcategories, classicTemplate.Subcategory);
-				cat.Templates.Add((TemplateBase)classicTemplate);
+				ICategory classicCategory = (ICategory)classicTemplate;
+				var cat = GetOrCreateClassicCategory(categories, classicCategory.Category);
+				if (!string.IsNullOrEmpty(classicCategory.Subcategory))
+					cat = GetOrCreateClassicCategory(cat.Subcategories, classicCategory.Subcategory);
+				cat.Templates.Add(classicTemplate);
 			}
 			return categories;
 		}