I always put mine below the waist, slightly behind the hip, but not on the bum cheek. I can't turn any further around to put it more on to my cheek, so that area seems to work. I also like to be able to see it when I go to the loo to make sure it's still there. I have put it on my stomach, but that seems to make it crease more.
If you have a sensitivity to the actual adhesive I'm not sure that putting it elsewhere will make any difference, but you can only try of course.
Have you tried on your upper leg/thigh? I think you can pretty much put it anywhere, as long as it's below the waist (at least that's what I've always been told). I think the theory about not putting it on arms, or above the waist, is because of the proximity to the breasts, but then of course that was when everyone was scared of HRT and breast cancer, so the thinking may have changed.