Models not showing up.

[Temreki]

So after looking extensively for a palm tree model that would fit my needs I ran into this

[url]http://www.dodbits.com/dod/index.php?option=com_remository&Itemid=100067&func=showdown&id=142[/url]

unfortunately, when I open them in hammer, there are no visible models or textures (not even the wireframe seems to show up)
they are "there" so to speak, since there is full collision and what not, but they just don't visibly render in Hammer or in game.

and i would also like to point out that this is the first time i've had this problem after successfully using multiple custom models, so I don't believe its a simple error on my part.

any idea what the problem could be?