Actually, I've been messing around since then.
I think the trouble was with me using process to move instead of fixed process. I almost works now, although I killed all movement 5 minutes ago... oh well.
I was however following his tutorial on 3d "soccer game". Now trying to make fixed work.
About is_on_floor and is_on_all: for what they're doing on that part of the code, is for triggering a normal jump or normal jump. So far I think it works as even back in Megaman games you had to move towards the wall... So for now I am imagining it working similar to that.