Could send me log files, please? (there are "output-(date+time).log" files in _logs subfolder). My e-mail address is contact@voidroom.com I'll check what's going on.
You deleted the game and reinstalled, so it's not dependent on in-game settings (there was an issue related to MSAA settings but it was fixed in the latest build, but still, if you deleted, this should not be an issue). I also don't think that there is an option in Steam VR that disables the game. Quick few questions that may also help finding, what's going on:
1. Does a window appear when you start the game?
2. If you move your headset, is the movement visible in that window?
3. What happens when you are in the game, you see everything gray and you press System button?