Very sorry to hear that. I’ve learned of some extreme performance issues on certain systems. The movement is supposed to be a framerate-independent 0.25s per tile, but on certain systems you get like 5 fps and it takes over a second just to move once. I have plans to mitigate that in the future but for now I wouldn’t recommend trying to run it on an old laptop or on browsers other than Chrome. The Windows executable should also be fine.