Steve, if you had new clips and the old molding still blew off, chances are the molding was deformed in such a way as to fail to grip the clips. When you get a replacement, make sure all clips are pushed fully down over the studs, (they should hook under the stud so as not to pull off) then make sure they spring towards the vertical part of the channel, just touching it. Finally, when you (gently) press the molding into place you should hear it "click" when seated. No mallets!
Hope this helps,
Rich
