Grips needed to be updated, so you can grip the Vive controls.
There was a hardware/software change in the driver.
In case anyone is having this issue:
Quote
'A developer just let me know that the problem was brought on in an update. "its a bit technical what fixed it for me was changing the code that detects grip to GetPressDown(...) instead of GetTouchDown(...) in the code, so I assume that recently Valve changed (or fixed) how they handle input with the grip button" He released an update to his game this morning and now it works fine. It was NEVER an issue with my computer but an issue of being forced to update when everything is working fine. '