Hello everyone! Although it seems so crazy, now I'm focusing on creating objects for The Sims 2. After reading many tutorials, I decided to make some objects and had no problems so far.

I made a chair based on the Club's base game and I have a problem with in-game selection. Strange as it seem, in the game I can only select (or use tools like recoloration) only in the part of the cushion (corresponding to the main mesh of GMDC) but I CANNOT SELECT the wood (wood mesh of GMDC). It's really weird. I tried to re-create the object from the beginning, but still happens the same. I didn't change the tile, so I think i don't have to draw the footprints (or I need?)
Please someone help me figure out how to solve this problem!
Thanks in advance.

That would be your bounding box. Export the whole of the chair, minus shadows, then reimport. Don't change any tickboxes regarding bounding boxes, just use the usual drop down box to replace the mesh parts. This will then build the bounding box around the chair/frame.

Thanks a lot... I didn't know anything about the criteria of SimPE for 'bounding boxes'. I could solve my problem thanks to your advice.
Can I ask you something else that bothers me? Everytime I try to make a mirror (or something with glass) I get a problem with the reflection (or blend in glasses). The reflextion doesn't appear and the only thing I can see are weird numbers and codes in a white background with a diagonal red line. How can I solve this problem? Thanks for everything, HugeLunatic!

Your welcome. The weird numbers with diagonal lines is because it doesn't have a texture linked correctly. Make sure your scenegraph is properly connected. I think mirrors all use a texture/reflection from the game and not custom ones.

Tutorials:Understanding the Scenegraph^wiki will help to understand how the package is linked together.

Thanks, I think I had the link between the SHAPE and the original reflection broken, I did fix it with the tutorial and now it works properly! I really appreciate your help.