HTML5 version: The spacebar key does nothing on the second level, it does not rotate the small grid. Browser is latest Chrome on Windows 10 (64 bits). Yes, I disable the ad blocker and force-reloaded the page, the problem still persists.
I had this issue before but I realized the smaller grid needs to be touching the bigger grid you are on in order for you to rotate it (Edit: And you need to be facing the grid)