Since i just got ignored last time here it is again:

bought through steam and when i try to install, an error comes up that says: "you must have at least windows XP service pack 3 installed "

the game then loads normally, until you try to create a game, then UDK.exe stops responding.

Windows Vista Home Premium (32-bit)
Intel Core 2 Quad CPU Q6600 2.40GHz, 2394 Mhz
ATI Radeon HD 3800 Series
4.00 GB RAM

also when i verify cache, it downloads a 6 byte file everytime.

it appears to be this one:
C:\Program Files\Steam\steamapps\common\orion dino beatdown\Binaries\uuuuuUnSetup.Manifests.

There was a buddy of mine who had this issue... he had to re verify and defrag the games cache... and if that doesnt work i might suggest reinstalling... Im terribly sorry to hear your having this major of a problem

Thanks for the advice but I have already tried all of these.