Have you ensured the hardware acceleration settings are cranked up in dxdiag and the advanced Display settings? Being that this is a server build, it may be set low or off by default.
I'm trying to install v25bG on 2k Pro w/ SP4 + Update Rollup 1, UR2, and latest nightly of UURollUp. I get the error "Error creating process <setup.cmd>. Reason: The system cannot find the file specified."