Force Renewal (FR) is pretty to easy to explain.
Each time that character activates, he gains 1 FP.
So with Vader's Apprentice, Unleashed (VAU), he starts with 2 force points. When he activates for the first time in the game he benefits from FR1, and thus gets 1 additional force point to use. This leaves him with 3 total. Now, providing that you don't use any during his turn, to move or re-roll, the next time he activates, he will gain 1 more force point. Now he has 4 FPs and can use Force Lightning 4 if he so desires. Or, don't spend any, and then next time he activates, he will have 5 FPs, and can use Force Lighnting 4, and have 1 FP left, or Use all his FPs to do Force Lightning 5.
There are a few things to be aware of. Sometimes VAU could be activated, or granted a turn, or an attack and he will NOT benefit from FR1.
For instance:
If he is affected by Stun/Jolt/Paralysis and is activated, then he DOES NOT benefit from FR1
If he is Dominated by Sly Moore, or the B'omarr Monk, then he gets a turn, but DOES NOT benefit from FR1.
More Info about Renewal can be found
Here in the Archives.
{edit} beaten by the rules master!