I'm using bullet on my game, all is working fine at this moment.
My first question is about the scaling.I must scale my objet 0.02f on each axis to not have slow motion.
Do It has one way to change the scaling ?
It is my understanding you must do the scaling yourself. As a side note, you must be doing your timings really wrong, or have a seriously low framerate. By the way, scaling down to 0.02 will likely make stuff go seriously awry as this is basically the minimum size Bullet allows as far as I recall.
All is working fine but when i have stair on the map, I must jump to up the stairs.
Do It has one way to get away this problem ?
It.. who? You'll have to write a kinematic controller sweeping your rigidbody somehow.