If the level has multiple chechpoints and you reset the level after collecting a later checkpoint in the level all the checkpoints that have not been collected will be collected.
Sadly I don't trust you enough to be mod, but we have a discord server where you can find games like this on speedrun.com plus all of the inkagames games can be found there too!
What happened in 4: There's an enemy that spawns to the right of the checkpoint, but wanders behind the checkpoint. If you hit the enemy before the checkpoint, then reset at the checkpoint, then the enemy respawns again, while the points from killing it don’t get removed when you reset. You can then kill it again to get double the points, and avoid having to collect every star, since getting gold only checks for score, not for whether you've collected all the stars. However, if you collect too many stars and go over gold, then it becomes silver and impossible to get gold (in v1), since it stores the silver as your best and won't change it unless you get a better score, which will still always be silver. In v2, it will still be gold if you go over gold (as a failsafe for infinite enemy spawners?) but in v1 it will turn to silver. Still collects all golds and achievements, so it’s allowed for 100%.
I dont think that sub 3 is that easy tho Afterall, this took me 2 weeks of strict grinding to achieve But thanks for the ggs 😁