Thank you for your kind comments and thanks for the live-stream as well!
As for now, you do not have many options to customize platformer games in GB Studio. You cannot change mechanics (gravity, jump strength, acceleration, etc) during game play, for example (these are like constants). I had to find out a workaround to achieve a way by which players can set jump strength while playing: there is an event called "bounce", which makes the player bounce. This option can be set by three levels during the game.
I know it is not an easy game, but I hope people will be able to master it and can get feel its rhythm.
I am so sorry that you had to download that buggy version. You are so kind that you tried it out! (By the way, I uploaded a new version with a few bug fixes.) Thank you very much for playing!