Stars need minimum day to be met yes, it's a soft time limit of days. It shouldn't be a problem to rank up early. I will check the issue with the end level check.
Viewing post in Isekai Parlor Simulator v1.6.2 (R18) comments
Don't know if they've been dealt with, but some of the dragon icons say "elves", dislike for certain.
Elsewhere in the clothes sections a few of the icons don't have their relevant icon, being a human silhouette instead.
Back to my last point about an overview, maybe it wouldn't be as necessary if in the Courtesan menu you could flick between sheets for each girl.
Sorry if they have been covered in the last two updates though