I was one of the anons who got filtered because of the framerate in your last submission. I tried it again with my two laptops and after the 60hz>240hz solution it worked with the fastest one. I also leaved it running for about 300 seconds to see if the time desynchronizes but it didn't.
Also, I found a rendering bug: in the input menu don't make any changes and just go back, the list of buttons will stay there.
As for the game, I really like this idea, this is the type of game that I hate being bad at, I'll definitely play it more! And speaking of practice, there's a little trick that can be made with the 60hz>240hz option. Since the game will be running slower than is supposed, you can run it at that speed on purpose as a practice.
I haven't tried the easy version yet thobeit.