THANK YOU!
After your reply, I found a lot of this on the V11 page, which I hadn't read. I'd only read the V12 page, sorry.
I had it set up on one event page with the enemy ID, plugin command, then erase event. I made the changes you said (keeping only one page with erase event) and everything is back. Now I have to change every enemy, which is annoying, BUT it's worth it for the advantages the update brings.
Thank you again for the help and quick reply.