Need help with NPC behavior management scripts

My one room contest game "Service With A Sigh" remains unfinished because I couldn't get the NPC customer behavior scripts to work consistently. Since I failed to write working customer behavior management scripts even though I thought it could work, could someone with a lot of advanced scripting knowledge have a look at the scripts and maybe think of how to fix it?

I could fork over the whole project as-is so there's no missing info or guessing about what I'm doing, but I'd rather only share with someone who wants to take on having a close look at it instead of me just publicly uploading it.

OK, I'll bite. When I saw your scripts earlier they actually look really well-written, clean, and not terribly long. So the problem hopefully doesn't go that deep, and it's sad that it all blew up regardless.