Having a behavior with the same name as one from the pack already in the game is the only way I could get something similar (but not quite the same) to your issue, so I recommend you delete your old Health behavior and try again.
Had a look through the behaviours I had, and health was one (from the old Side Shooter pack I believe). Removing it and then imported your pack and it did the trick, thanks for the assistance Luyren!
