Hello! I understand your frustration but most likely your track has wrong checkpoint placement. Please make sure that all marbles go through the same set of checkpoints in exactly the same order. Also please join discord for better support :)
I think if you add the game to collection you will receive info about updates. Meanwhile you can try the browser version. The bridges will be redesigned in future versions.
Hey thanks for the suggestion. Running the game in window mode with different resolutions is planned. If you would like to make more suggestions, please join the discord community server! Enjoy!