@space-wumpus Thank you so much for the feedback. I completely agree with your points made. There is a sweet spot with crushing enemies right when they spawn versus just before they spawn. So sometimes you will think you crushed them but were just early, this then pushes them upwards onto the block so that they don't die inside of a fallen block (otherwise you could just keep placing blocks where they are spawning and then they would die inside of fallen blocks). I believe this is the issue you mentioned with them spawning instantly. I'm not sure the best way to improve this in the future but open to ideas!
That is also a rare bug you found. I am not sure how to replicate that but if it happens again, it would be great if you could send a screenshot of the console window in your browser so I can better understand.
Also, awesome score! I'm nightfire on the leaderboards so you have me beat. I'll have to improve :p