You don't need a mod to unlock the gallery.
Delete the file "gallery.rpyc" inside game/ folder.
Edit the file "gallery.rpy" inside game/ folder (you can do this with notepad).
change the values of "define ga#=0" from "0" to "1" (for the 0.29 there are #58).
Open the game and start a new game or load yours.
I'm stuck near the beginning. I turned down the Frank route and beat him in the library contest. Now I can't find any accessible content. I tried advancing the day and checking different places at different times of the day but I can't find anything. I read through several pages back in this thread but didn't come across any solutions. Can someone help?