[Silveras]

You may want to limit the books used in your game to ones that everyone has, or for each player to use only books that you and they both have.

One issue to watch out for is the "random to random" scenario. If you don't keep careful control over the "version" of the files being moved around, it is likely that there will be mistakes .. such as old files being used instead of the correct one... and changes could be lost or backed-out.

You may want to limit updates to between sessions. Trying to manage it during sessions will slow things down. The players' use of HeroLab is for "live" calculations, while the GM's can be a little different. You and they can each modify your own copies independently, and not worry about sharing the POR files except at specified intervals (such as when the adventure is over, or at level up).

Discrepancies like ammunition used, potions used, charges used, and such can become hard to reconcile. If your copy is the master, then don't take updated files from the players.. have them email you any changes that aren't part of "in-play" (such as skill point allocation on level-up) and export your master copy to separate PORs for them. You can work out disagreements on accounting by email between sessions.

If you intend to treat their copies as being the "master" copies, then you should only accept updates from them.. and not send any back. A "master" implies that it is the authoritative version ... in which case, updated files should only flow from the "master" to others after being manually updated.

If you intend to pass updates around between any two people, then there is no "master" really, and the chances of disputes are higher.