does exist a complete B3D file format information?

Not sure, try these.

http://www.blitzbasic.com/sdkspecs/sdkspecs.php
http://www.geocities.com/drago_blitz/B3dFormat.html
http://code.google.com/p/max-edit/source/browse/trunk/plugins/fileb3d.bmx
http://www.blitzbasic.com/codearcs/codearcs.php?code=866

Also, this has an extension format.
http://www.onigirl.com/pipeline/