A. after every switch the game started lagging a little more and after a while attempting to switch to triangle caused the browser to soft-lock, indicating to me that switching is performed by loading a new iteration of the requested form every time without unloading the active form.
B. I think you misunderstand, the problem is that a hit is detected before the player character is close enough to one of the spikes for it to actually count as a hit. (as the spike wheels other than the last allow one to remain outside their radius, I don't know if this problem exists with the other spike wheels, and they may be too small to properly test this)
C. Thanks