Thanks for playing and rating my game and I'm really glad you enjoyed it. Had a look at the bug, and I think it actually happens every time without fail. Actually every level repeats the last line of dialogue for that level on repeat, however, every other levels last line is set to an empty line which triggers Mr. Skeleton and the UI to disappear. I forgot to add that last empty line for level 19, however, level 19 should be fully playable anyway. You don't need to wait for the dialogue to end before you make moves. I fully agree with Mr. Skeleton making noise when he talks, there were a couple other sound effects that would have been nice to add as well, but sound effects are not something I've worked on before. The space-bar issue should really be made more obvious too. Unfortunately I'm not in a position to fix the bug at the moment, but I can add a line to the game description saying I'm aware of it and that it won't prevent you from preceding until I can fix it in a few days.