Really cool concept! A few things:
Right when the game started, I only saw white. Turns out, this is because I moved my mouse right away and didn’t notice, and since everything is fully white, I couldn’t orient myself back into seeing the game :) That’s very minor though.
SPOILER ALERT (since I don’t think I can do spoilers in itch.io’s comments?):
I figured out you don’t actually need two instances of the game to complete puzzle number 5. Steps: Go near door -> save (red) -> stand in between the two buttons and press them both -> save (blue) -> load -> interact with door. If this is unintended, then it can be fixed by simply moving the two buttons farther apart. I actually have no idea how to beat it the intended way :)
SPOILER ALERT OVER
Overall, a cool concept for sure! With some more time and QOL improvements, I could see this getting more fleshed out.