If you tried everything then it is not looking very hopeful. Maybe someone with a Huion tablet will come up with more advice.
Give the version of Gimp you are currently using, OS and maybe the tablet version.
Edit:
Did you see these, maybe something in there applies
http://www.gimpusers.com/forums/gimp-use...ssage88192
and
http://www.gimpusers.com/forums/gimp-dev...ck-request
Give the version of Gimp you are currently using, OS and maybe the tablet version.
Edit:
Did you see these, maybe something in there applies
http://www.gimpusers.com/forums/gimp-use...ssage88192
and
http://www.gimpusers.com/forums/gimp-dev...ck-request