Thanks for your Review.
You are correct, as this being a jam to replicate PS1 console games, we opted to make it authentic controller-only.
The you can map the keys and flip Y in options->gamepad, you can reach options from the main menu or by pressing the option button of your controller mid-game.
You can record the past 10s via F10 and post your situation. Then maybe I could repro that and fix any issues.
Thanks for reporting that all, very appreciated!