It's mostly flawless in Multiplayer, but it does have a few quirks.

If player 1 is inside of a factory building when it is removed by player 2, then player 1 will remain inside of the building, un-fazed. If player 1 exits the building, they will reappear where the entrance to the building formerly was, despite the building having been removed. However, if player 2 places the building in a new location, and player 1 subsequently exits the building, then player 1 will reappear at the building's current entrance.
Not sure if this is intentional or not, but I can see it being useful in some situations. Great mod btw.

This is intentional, so players working inside buildings don't get disturbed when the buildings get moved by players outside. However I might consider teleporting players out when the factory actually gets killed.

Maybe restrict players from destroying the building while someone is inside?