strange... the poly looks like it has a transparent bitmap added to it, or maybe is a flipped face or maybe you didn't add texture to that poly at all.
you didn't use gravminds app that bypass's errors did you?
also did you add grenades as starting equipment? that also causes exceptions on maps.
Edited by ally on Sep 1, 2011 at 06:36 PM

i remember you showing a map problem when you were trying to add glass squares
to the ground. is this the same part of the bsp ground?

sorry man i have googled around and checked the normal places i would find answers but
this time i can't, hopefully someone else has seen it before..

I'm kind of going out on a limb here, but it's probably some geometry error that seems to be making a reference to -1 for something, maybe sky? You should try using adolif2's bsp fixer program which you can find here: http://forum.halomaps.org/index.cfm%3Fpage=topic&topicID=38668