Interesting idea, but I encountered a few bugs: You can click "roll the dice" however often you like, accruing endless jumps. And it didn’t seem to display the "jumps/attacks given" at all for me.
No, in fullscreen I only get a quarter of the screen displayed (similar issue with other games). I do see the text itself, but no value next to it. (Can’t seem to post an image here, sorry.)