Basically, I had the game running fine, then installed the Development Build. After that, the game would load as a black screen, and stopped responding. I changed back to 'none', loading it exactly how I had it set before the Devbuild, but it still did the same thing. I am launching the game in -nobenchmark to solve a previous issue, though even with this off it still blackscreens. I have also tried verifying the integrity of the game cache, which again did not help.