Thanks for the feedback! A new build of the game has been uploaded that I hope will resolve the DualSense controller issue, the game starts in windowed mode now, and fullscreen can be toggled with Alt + Enter. I changed the UI scaling to match the screen's height instead of width. Unfortunately, I do not have access to an ultrawide monitor to test if this fixes your issue.
Additionally, I fixed a bug where certain enemies get stuck in their hitstun animation.