I changed the key "R" to be the rotating mode but it does nothing but freezing the cursor in place, the cursor doesn't change icons either like it does when the rotating mode is working properly. I can make it reset the rotation or rotate right/left but when on rotating mode it does nothing, I also deactivated the pick layer default function for the "R" key

I changed the Canvas Input settings Rotate mode to 'R + Left Mouse Button' with no problem by assigning it and then reassigning the Select Layer function to Shift+X+Left Mouse Button (or something else not in use). How did you 'deactivate' the Select Layer function?
Have you checked in the keyboard shortcuts to make sure that 'R' is not used in there because it may be, depending on which shortcut scheme you have in use.

So i got it to work making it a "Mouse button: R + right click" like you said instead of the "Key Combination: R" I had.