[3ds Max 2009] Ignores Keys at Rendertime !

[Hangs]

Hi,

3ds max ignores some of my animation keys when i render more than a single frame, and he uses the value of the first rendert frame for all.

The main problem is a counter i have in my scene, its a Maxscript which changes a Textspline with numbers. When i hit play in vieport he do everthing correct, when i hit render he renders the first Frame correct and then use the same value for all other frames and dont take the new values from max script.

I had the same problem whit selfillumination of Arch&Design Materials, but there i usesd a Lume shader to fix it, but why Autodesk let you set Keys for values he dose ignore at render time ???

Is there any flag or button i have to klick, or what is the problem here ?


Thanks

Edit: Some more infos to the maxscript
Its a helper whit a costum Attribute which is the value i animate. The script is a custom controller in the Y positon.
Script:
tmp_int = param_extern as integer
tmp_string = tmp_int as string
text_extern.text = tmp_string
param_extern