I have a very elementary question for all you experienced 3Ders :

What do I have to look out for when modeling an obj for Studio?
My case: I'm modeling a little room in Blender 2.49.
I can get the geometry imported just fine into Studio.

But two things are missing: I don't have the ability to select say, a seperate wall even though it started as a seperate object in Blender (I want to be able to deselect walls for more camera freedom).
And I can't get all materials (only some) shown under the Studio surfaces tab and don't get the ability to mouse over the material zones too.

So I'm not totally hopeless but also not quite there yet :D