Sorry to hear it. This issue popped up randomly back in the original non-web version as well. There is a keyboard shortcut for the button P that tries to re-draw the UI to help a player get unstuck, so if you have the patience for it, give it a go.
You didn't miss it! :D I added it after your first message. It was in the readme.txt of the original windows version, but I'd forgotten about it until you brought the issue up, so I decided to add it to the description as well for any future players. I hope you have fun with the game!
