You are correct, NO Teamwork in trial version.
The way it works is after creating a SOLO project (.pln) you have to SHARE THIS PROJECT... then team members can SIGN IN to this and create their own unique LOCAL COPIES. Changes are SENT and RECEIVED to the HOST file and in so doing, update that local copy.
Teammates can continue to work with the LOCAL copy until they either want to CHANGE THE WORKSPACE (add or delete Layers, Stories, etc) or SIGN OUT.
There's the nutshell version. Plenty of idiosyncrasies, but that's beyond the scope of this answer.
Duane
Visual Frontiers
AC25 :|: AC26 :|: AC27
:|: Enscape3.4:|:TwinMotion
DellXPS 4.7ghz i7:|: 8gb GPU 1070ti / Alienware M18 Laptop