UPDATE: Yep, HoW seems to work alright in the latest (and final?) version. Installing the 1.11 patch seems to have gotten rid of the odd AI behavior, when it comes to HoW. Thanks, guys!
EDIT: I have just applied the latest 1.11 patch to my Steam RoP; I'll test the scenario again soon by starting a new game... hopefully the HoW decision works as intended in the latest version
Sorry for the necromancy, i.e. resurrecting a long dead thread, but in the Steam version of RoP Gold, I am having this problem with the Silesian War scenario.
I am guessing this was never fixed, correct? That not being able to use HoW in regions you can't own feels a bit counterintuitive.