I have the impulse version, bought King's Bounty AP through impulse nearly last year.
Got crossworlds as an add-on, (which forced me to redownload and reinstall King's Bounty AP, since they use a different directory now).
I can't apply the hot-fix though. It says I don't have King's Bounty AP installed or something of that nature.
I guess I have to wait for impulse to update it on their end.
As a side note, I've noticed a bug that occurs occasionally when I am fighting with orcs (I hate them... they are so overpowered to fight against now), where it says some script error and "abort/retry/ignore". I ignore it, and all seems well.
Does this hotfix patch that?