Hey there.
How to import a .X or .3DS Model in my 3d world studio level?
Didn't you just ask this question here?
http://www.blitzbasic.com/Community/posts.php?topic=77797You even have answers you haven't replied to.
You need to run the ConvertModels.exe which comes with 3D World Studio. It creates a .smf files of your .X and .3DS files which can be used in 3D World Studio as a model.