Glad you enjoyed it and thanks for the detailed feedback!
For the controls, You can actually use C and X instead of Z and X to switch the order of the buttons (and X==V). I liked your idea of having swapping vertically and rotating with left/right at the same time, but I think it might get annoying to unselect (or put away) a piece. Maybe using X+Z to automatically unselect it or mess with the storage order. I’ll need to test it a bit before adding it to an update.
The progress should be saving when the level is done. I tested it 3 times on the browser (firefox + windows) and once with the downloaded version and it seems to work fine. This could somehow be pico-8 itself not properly storing the save when the save data is updated. It’s programmed to update the save data right after it detects a finished level and there’s no calls that clears a level’s completed status. (except save clearing, which is only on the main menu and requires pressing it 5-ish times)
I don’t think it’s possible to prevent key-repeating per button, not without some code that won’t fit into this game due to pico-8’s limitations. I’ve had both people who wanted repeating keys to be on or off (turned them on in version 1.1) I might try to squeeze in an option though.
There’s probably a lot I would do for this game if I had more tokens (though it would have made Infinimoes be in development for MUCH longer).
Unfortunately I don’t know what would cause the audio not to work. There is a sound button on the right that could be muting it (I think the sound settings are shared between most pico-8 projects).
Your game, Sticky Chunks, is pretty neat (even if I’ve lost interest in games revolving around highscores over the years). though I noticed the version that I could play was different from the one in the video (that looked like it was the pico8 version).