any way i try, i cant get code to work for grind+jumping levels

(its for a scateboard game)

Problem #1 Rail Grind:
the rail is dense
you click grind (only 1 space away mind you) and you can get on, then you gain exp

but i want it to be where you can fall off the rail @ random intigers

Problem #2 Jumping:
i want to let ppl jump over any dense objects, and get exp for jumping but where they can set how high they jump, the higher they jump the risker it is they fall and die


hopefully this will make for a good game but i need help!!!
:(
help please, ill give u credit on hub