I tracked down your GitHub profile so I could play on my mac.
Unfortunately, I think there's a bug in your input code, because clicks don't seem to be registered in the correct position on my high dpi display.
I took a peek at your viewport-to-world code, and it looks like you could benefit from Bevy's built-in functions for doing this.
I wasn't really able to figure out what was going on though. But there certainly were lots of things! Good job getting something submitted. A bit more work on the itch page might have helped me out.