strange error with Scriptable AS Studio App (SDEF)

Hello!

Today I want to make my AS Studio App Scriptable with a SDEF File.
OK, I added a new Objetive-C Class for handeling the script commands. To test this I used a new AS Studio project. After some tries it worked very well. I can access my AS-Studio App with an extern Applescript. (At this moment I was very happy).

Now I integrated the same class and sdef-File into my “real” App. But after I build it, I got the Message: “AppleScript Error: -1708”
Now I was really confused. I debugged the project and found the problem:
If the myproject.applescript file don´t have any event handler or functions inside, everything works well. But if only one event handler is called in the myproject.applescript file I got this error und the event handler was´n called. But I can call the Objective-C Methods from outside.

My question is if I can use sdef inside a AS-Studio App? I also need to call the event handler inside my myproject.applescript file. Is there a solution for my problem?

I would be very happy if someone can help me.

Greetings, Matt