Upon further testing, the Yes/No message box
does work just fine outside of the beginning of the event... huh.
I think it might have to do with the face that I was trying to show the message box before the event loads the opening map (flying airship)... which means if I load the Black Room used for the "meanwhile..." tects and falling down the Tower of Babil, it should function properly.
EDIT: It worked! Turns out you HAVE to load a map before showing a Yes/No message box during the Opening Events! I can't seem to get the "If No" section of the event to function (basically loading a map, and setting a flag to allow players to skip my edited Mysidian Legend IN SPAACE visual in case one of the battles manages to get them killed), but that's a story for another day.
EDIT2: Seems the Yes/No Box behaves differently during the Opening events. It won't go through the event items in the "if No" section, but it will seemingly skip the next 1 event item. So picking "Yes" sets flag 127 and skips my M.L.I.S. visual, and picking "No" plays it! Not sure why it works that way, but it's essentially doing exactly what I wanted to do.
I'm happier than a pig in shoes!
Huh, that's interesting.
Anywhere in the opening events, or only as the first event item?
While it isn't the first event item, it's definitely the first message the player would see. The first 22-23 event items are the adding/removing of actors to properly set even experience distribution since I made the two autobattles into normal fights.