2 things i can suggest:
get the props library vmf (downloadable off of this site). it has all props already placed in it, so you can just copy/paste into your own level.
the other thing: if you can't get the top model to work, just get a bottom model and rotate it by 180 degrees. they are practically identical to each other.
I feel like a huge idiot...sort of. I noticed when clicking on a present I made earlier it wouldnt run a search through the model browser UNTIL I clicked on the +mdl files catagory on the top of the window. Yeah. So I'm not sure if this helps anybody else but it wont run a filter search EXCEPT on the highlighted catagory if that isnt selected.
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