Hi there long time since my last post.
I have a question how should I correctly map this?
or should I better correct the geometry? and how to?
Re: How to map this?
Do you mean the artefact?
--> Maybe it Micha’s work-for-all-workaround time again 
http://forum.asgvis.com/index.php?topic=7596.msg44057#msg44057
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How did you model this?
These surfaces look as if they were just joined together. You could try to merge them before baking Micha’s wavefront cake 
Re: How to map this?
no its not a polysurface, its a networksrf in a single process. i’ll work around michas tip if that helps