At which point of the teacher's quest are you stuck? Buying the diaper pack I guess?
You're not the only one reporting me that you can't close the shop UI but for now I didn't reproduce the issue. Can you tell me if you're playing in full screen and in which resolution?
For the bar, if you're low maturity, an event should trigger right as you enter. I'll try to reproduce it to see why it didn't trigger. Same thing ,the guard should have stopped you beforehand.
Edit: Nevermind, I found the source of the bug. I guess you used the "return to title" menu button at some point during your play and I discovered It affected some backend functions. Won't dive into it much more, I'll quickly fix it. To prevent the bug to occuring until I fix it, avoid using the "return to menu" button.