Sounds like an infection around your abutment - they generally cause skin irritation and sometimes itching.
Unless, like James said, you have a titanium allergy, which is fairly unlikely.
Removing a BAHA is not easy - especially once it's calcified into the skull. From what I've read, a piece of skull would have to be removed along with the abutment.
Generally if someone decides the BAHA is not for them, the doc just removes the abutment with a screw driver and leaves the titanium rod in the skull. Eventually the skin on the scalp grows over the abutment.
Before you do anything drastic like letting your doc remove your implant and move it, you definitely need to get a second opinion from a doctor who does BAHAs.
If you need to find someone in your area, go to
www.cochlearamericas.com and search under "Find a Clinic".
Jan