CSharpSyntaxLanguage + MyOwnLanguage merged.

private void CreateDirectiveXmlToCSharpLanguage() {
    // Load the two languages
    language = DynamicSyntaxLanguage.LoadFromXml(Program.DynamicLexersPath + "ActiproSoftware.XML.xml", 0);
    // DynamicSyntaxLanguage cSharpLanguage = DynamicSyntaxLanguage.LoadFromXml(Program.DynamicLexersPath + "ActiproSoftware.CSharp.xml", 0);
    ActiproSoftware.SyntaxEditor.Addons.CSharp.CSharpSyntaxLanguage cSharpLanguage = new ActiproSoftware.SyntaxEditor.Addons.CSharp.CSharpSyntaxLanguage();

            CSharpSyntaxLanguage csharp = new CSharpSyntaxLanguage();
            
            DynamicSyntaxLanguage gwTemplate = GetGenWiseTemplateLanguage();

            csharp.IsUpdating = true;
            gwTemplate.IsUpdating = true;

            // Add a highlighting style
            csharp.HighlightingStyles.Add(new HighlightingStyle("TplDirectiveDelimiterStyle", null, Color.Black, Color.Yellow));

            // Create a new lexical state
            DynamicLexicalState lexicalState = new DynamicLexicalState("TplDirectiveState");
            lexicalState.DefaultTokenKey = "TplDirectiveDefaultToken";
            lexicalState.DefaultHighlightingStyle = csharp.HighlightingStyles["DefaultStyle"];
            lexicalState.LexicalStateTransitionLexicalState = gwTemplate.LexicalStates["DefaultState"];
            csharp.LexicalStates.Add(lexicalState);

            // Add the new lexical state at the beginning of the child states...
            // Remember that with an NFA regular expression, the first match is taken...
            // So since a < scope pattern is already in place, we must insert the new one before it
            csharp.LexicalStates["DefaultState"].ChildLexicalStates.Insert(0, lexicalState);

            // Create a lexical scope with a lexical state transition
            DynamicLexicalScope lexicalScope = new DynamicLexicalScope();
            lexicalState.LexicalScopes.Add(lexicalScope);
            lexicalScope.StartLexicalPatternGroup = new LexicalPatternGroup(LexicalPatternType.Explicit, "TplDirectiveStartToken",
                csharp.HighlightingStyles["TplDirectiveDelimiterStyle"], @"<%");
            lexicalScope.EndLexicalPatternGroup = new LexicalPatternGroup(LexicalPatternType.Explicit, "TplDirectiveEndToken",
                csharp.HighlightingStyles["TplDirectiveDelimiterStyle"], @"%>");

            csharp.IsUpdating = false;
            gwTemplate.IsUpdating = false;

            syntaxEditor1.Document.Language = csharp;

using System.Reflection;
using System.Runtime.CompilerServices;
using GenWise.Framework.Templates;

namespace MyProject 
{
   public class <% U.Quote(Options.ClassName) %> 
   {
   }
}