A quick check of the skills descriptions seems to suggest that many of them come under barge skills, for example the AT-AT. A more definitive answer on the rules page may be helpful.
Vehicles will be modifed by the 'Vehicle-Barge piloting' skill (at least time-wise). Any combat skills have not been implemented yet since there is no combat. But presume something along the lines of the combat skill being able to hit better, do more damage etc. Mouse over the skills and it should give a brief description of the skill.