[x] Backs need locked_loc_vars in Back:generate_UI()
[ ] Stakes? (seem pretty static, not necessary?)
[x] Stickers
[ ] Challenges
This seems very awkward to make work, each custom rule is its own localization entry, with a single loc var. Looks like ideally we support multiple loc vars for each rule.
Challenges don't seem like a priority right now
Back:generate_UI()