Is there room to have a 100% category for the challenges if all the additional side challenges are done?
Could probably replace the "100%" and "100% multiplayer" categories with these as there's already a seperate Any%/100% toggle for each challenge leaderboard? Really I think it makes sense to split Challenges and Singleplayer levels on the all level leaderboard, or at least get rid of the two 100% categories as they're covered by "singleplayer" and "multiplayer" already (or get rid of the toggle options, but it's confusing having both).
It's possible to completely reset your save by turning off steam synchronisation and deleting UserProfile.STU but what also locks the later challenges unfortunately, if there was a way to edit the STU file then that would solve the problem.
https://mega.nz/#!Uqh0CYLY!TiK0n8CnGEQdSyD-LijnyC-Lz_U9iBUASRqaC2vSZdo Here I've made a Save game with all the challenges unlocked but no bonus objective completed, with this 100% challenge runs become viable