Alright, I'm trying to build up a single speed MTB conversion, and I can not manage to install the bottom bracket. Maybe I'm being a complete moron and either have the wrong parts or am trying to stick them together incorrectly; but I think I've checked everything pretty carefully and they really should be compatible, and I've (successfully) installed a bottom bracket before so I'm pretty sure I'm doing it right. The BB is new, but the frame I bought off CL and although the guy seemed pretty trustworthy I'm worried I may've been had. At the very least it may need to be tapped, etc, which is something I know absolutely nothing about and probably service money I really don't have to spend at this point.
Okay, here are the pieces:

Frame - 2008 Kona kula supreme. here
Bottom bracket - cheapass truvativ here (it's 113 mm, though)

pictures of the bb shell in a few minutes.

The BB starts to screw in, but after a rotation or two gets harder and harder to turn. Either side. I (gently) tried to force it on one side a bit, but got worried that I'd strip the threads and chickened out.
I know it isn't an ideal build, but it's what I've got for now.
Any help/suggestions are greatly appreciated, thanks!