Don't get me wrong I'm not trying to be dismissive or insulting. I'm just searching for ideas to run these enemies in an intelligent and logical manner. My group has already questioned why none of the enemies they encounter ever raise any kind of alarm or respond to epic fights happening in adjacent rooms (examples include: Thistletop, the Graul homestead and Fort Rannick).
The meta game answer is because if the entire location becomes alert and the bad guys send everything in at the party (as they really should do), they would be dead. The group needs to face these challenges in isolation from one another. How to accomplish this without straining my groups already stretched suspension of belief is puzzling me.
My group didn't face these things in isolation. When they started their first fight inside Fort Rannick, on the ground floor (after sneaking in through the basement and using a Silence spell during the one fight there, so it didn't attract attention), all the other ogres inside the ground floor came running. It just took a few rounds to get there, so they were able to handle them a couple at a time pretty easily. This has happened in a few areas of the adventure path so far.
In some parts of the adventure, it specifically says that certain groups of baddies ignore disturbances outside their rooms for specific reasons. Other than that, you do have to remember that some of them live in noisy areas, so they might not recognize fighting noises for what they are, unless a bad guy intentionally raises an alarm. Think of it logically for each area, and don't be afraid to combine fights occasionally, but make sure it takes a couple of rounds of saying "What was that?" and deciding to come, along with traveling time, before the second group arrives to check things out.