First thing I would recommend is not spraying down the skin with the oil/apple juice mixture. There is plenty of fat in chicken skin. No need to add more. And spraying the skin will just keep it from rendering out the unwanted fat and other tissue, thus preventing it from crisping.
The other thing I would suggest is to turn the heat up on the chicken. Low heat + smoke = rubbery and tough skin. I do a lot of barbecue, and I never find any compelling reasons to do chicken low and slow, unless I want to make pulled chicken, at which point the skin is useless to me anyway. I prefer to make chicken in the 325f range, as it turns out much better skin at that temperature. You can even get away with cooking at a lower temperature, then cranking the heat up to finish the skin.
Finally, I would suggest ensuring that the surface of the skin is very dry, and has been salted (not heavily, just a bit), before putting it on the cooker. This, too, improves skin texture.
The TL;DR version:
- Quit messing with it while it's cooking.
- Turn the heat up.
- Dry and salt the skin before cooking.