I'm not the dev but I'll answer to the best of my ability.
One thing to note as well is if you apply the patch I shared earlier, you will need to let the game load a bit on the menu. If you see the adult Lydia and you can't click anything, just wait, it's loading.
Worked totally smooth for me, but this game is based on Unity, and sometimes the performance is a little bit off. I'll report the white screen bug to the dev, as it others are having it as well!
There's quite a few, there's a boy you babysit or break into his room at night. There's also the boys in your house and one you can date in the church.
Literally no idea how you're missing the buttons on the bottom left, to save and shut down, but they are there:
View attachment 850372
Just attend their classes
Go to school and attend their class