Hi Jean,
I have not tried the script yet, the link was just to try to show what I was trying to do. I do have a question though to see if I did this right.
Here is what I did based on the solution you provided:
1. Get device accelerometer values and store them in a vector3 every frame.
2. Get the camera's X axis with "transform direction" every frame
3. Use a "vector3 operator" to multiply the accelerometer values by the transform direction values every frame.
4. Take the vector3 from that multiply operation and use it in the add torque value every frame.
I tried many different variations as well but this is the one you suggested I believe. All the ball does (even in the default camera view) is move in one axis, based on the camera view but is always a different axis when the camera turns. It's inconsistent.
If we can't get this going it's ok you don't have to do a sample, I already have a joystick working with the camera turn. I can just take the tilt function out. It would be nice to have a tilt but it is not necessary. I know you are very busy and I don't want to bother you with my stuff too.