Congrats on beating the game! You can get 100% before you enter the Looong Gallery, yes. 🙂 I hope you're enjoying TaiFab!
If you want, there are hints below for the missing puzzles you mentioned:
.
.
.
.
.
.
.
.
.
.
Have you tried going behind the counter to talk to the innkeeper?
Have you tried sleeping in empty beds?