I'm having a problem with a wardrobe I converted from the Sims 2.
I cloned a wardrobe from Supernatural, assigned the joints properly and there are no problems in the game except for the gap that happens once a sim opens the wardrobe.
I tried editing the mesh, thinking that maybe the problem was that the doors weren't placed in the right place but even after editing the mesh, the gap is still there.

Edit: Apparently the problem was the new doors weren't as wide as the original doors. Once I edited the doors' mesh to be the same width as the original doors problem solved! No gap! :D