I like the blue field as a way to add a kind of restriction to the interact-with-past-version platform game mechanic. I did need to restart some levels a few times due to not knowing which buttons affected which doors and starting to have more clones on screen than I could handle, but I would say that this game has solid mechanics. My main suggestion would be to have a way to tell which buttons corresponded to which doors, a way to see the whole level at once, and a way to reset without leaving a clone (since it's already possible to do that in certain areas by dying).