Get the Imperial Assault Campaign module for Vassal from http://www.vassalengine.org/wiki/Module:Star_Wars:_Imperial_Assault
The next Total Solar Eclipse holiday in 2024 in USA? See you there!
about keeping the tokens and possible minions hidden until the door is opened to that particular room?
The reserved groups already are hidden and only deployed by the mission events.. So not change there.
Otherwise, if you agree with the rebels to make the campaign more of a RPG instead of competitive, then try it. But many mission briefings refer to terminals or tokens the rebels need to interact with or destroy, and not seeing those from the beginning will require you to read and reread the mission rules a lot of times throughout the mission and increase the time limits.