pf/sfx
Okay, those are the few I kind of expected. Ganondorf's Tower uses a buttload of models for the blocks, and Bowser's Keep is iffy. I can't really do much about the Tower, but I'll see if I can optimize BK at all.
Not really sure about Outer Wall. I'll check it out. Last time I checked it was working fine, it may have been a one time thing though, like Flat Zone. Do you remember what costumes you were using? That could also have been an issue.
Walls where exactly? On the sides of the platform? I didn't make the stage, I just redid the textures.