Help for a novice modder

Hail and well met. I'm looking for a bit of help on some customization I'm doing to the game for a friend of mine. Basically I've created an innate shapeshifting ability for him so his barbarian can turn into a bear. I've figured out how to grant an innate ability on shift and how to remove it (so that shifting back and forth works properly).

What I can't figure out though is how to clear a memorized instance of an innate ability. What I want to do is give an ability only usable while he is in bear form. I can grant it as an innate ability when he shifts into a bear, but the problem is, even if I set it to be removed when he shifts back into natural form, the memorization is not removed. Meaning he can then use it in human form, and just as bad if he keeps shifting back and forth w/out using it up it stacks memorizations.

Does anyone know how I can force the memorization to be cleared on the shift back to natural form, or an alternative approach to granting the ability only while in bear form. I can post my files if anyone is interested. Thanks.