_rotation ,maybe

ok here is my 1st post …

i have a mc and i would like to rotate it like a volume dial on a radio turn it to the right and let go and it stays there,turn it to the left and it stays there …no volume at all just the script to make this (_rotate )
so basically .10 20 30 are the numbers located left top and right
on a circle …when i click on number 10 i want to be able to drag it to where the 30 mark is on the right …i think you get my point …check the attached file …
cheers

**************edit ********************
anyone with some advice??:p: