make a trigger. Make initial value for visible = invisible.
Then when character overlaps it shrink him as much as you want set size = player.width/2 & player.height/2. When he gets over another trigger do multiply by 2. Found a simple way. You can even just scale it.
And f you want him to run by himself just use platform simulate movement for a few seconds or untill a point is reached.
can't post links yet but just copy paste this...
https://dl.dropboxusercontent.com/u/3961018/smallbig.capx
nice, this is indeed what i want, but i need to make it smoother, like
from 100 to 50, every step i take decreases 1
so, 99,98,etc.. until i reach 50
how can i do that?