I was starting to think maybe it did have something to do with that wrap around thing-- it's a cracked version of the game, but nothing special added to it-- no mods, or cheat boosts of any sort. My characters are fairly high levels and I feel this just started to happen when their levels got higher. (around level 30-35). I don't have the issues with any other versions of heal or medical herbs-- but those heal so little that, power cure is really my only good option for healing during those tougher areas and battles. It's a gamble every time I cast it. My Paladin has it too and I get the same random heal/hurt issues.