Hi, I'm having a similar issue; the text doesn't disappear, but the window doesn't become a bubble or anything either. I didn't adjust any of the default parameters, and tested it in a blank project. Here is how my event looks. Any help is appreciated! :)
EDIT: Nevermind, I figured it out! I wasn't matching the event name to the message window's name! So sorry! Thank you very much for this plugin, I love it!