There is a sub-forum dedicated to each Adventure Path here on the Paizo messageboards. Each such sub-forum will have pinned to its top a series of threads dedicated to that AP (one for each book). Those threads are intended for the GMs running those APs, for troubleshooting and the like. (Obviously players should avoid them or they will be spoiled.)
Kingmaker is in an odd situation, in that the original KM and Kingmaker 2/KM PF2 APs each have their own sub-forum. (Unlike each iteration of RotR and CotCT.) If you're running KM2, you might still find some useful information in the KM sub-forum.
Other useful threads to check out in these two sub-forums: the "community created stuff" and the Obituaries threads for the individual AP. They might not be pinned (and I'm not sure if they exist for every AP). Again, they will contain spoilers so the players should avoid them.
The Obituaries thread for each AP can be illuminating reading. If a particular encounter is constantly producing PC deaths - or even TPWs/TPKs - then it's a good indicator of where to be careful. The Obituaries can also be hilarious reading. :D
Good luck with running KM2! :)
