I simply removed Shapeshifter Rebalancing. Granted, shapeshifters need some rebalancing, but I think this was a case of a cure that went too far: that shapeshifter might as well have cast Summon Munchkins.
But this may well be a bug, as the pair of 20 HD werebears were supposed to last 4 turns, according to the readme. I took that fight the first time to over 20 turns, and the werebears had gone from heavily injured to freshly washed, deoderized, and dressed to kill. They were in it for the longhaul.
I certainly don't fault JCompton for his scripting of the attack, which had the various summonings turning on other members of their party before they found us. It was a 1-in-a-1000 chance that we were caught by Kelsey's nemesis and her hirelings that second time literally outside one door of the CC. The scripts triggered, but we then ducked inside, and emerged down the block. It was amusing to read the way the attack ran out, with the hirelings dead, and just three of the summons still alive, plus the mage. It is in all respects a quality mod, and heads above any of the other NPC mods I've tried.