I need some clarification for my gaming group, I usually Judge and my friend was running a Han Solo with Gunner and push the limit, is it possible to Launch your first attack, re roll the dice with Han solo, have all hits evaded so then gunner kicks in re attack, then use your target lock to re roll dice in your second attack, then change any focuses to hits? Just want to make sure theres no double rolling going on

Looks OK. As long as your not re-rolling the same dice with the TL and Han's ability on either attack it should be fine.

Yes, as long as Han isn't using his ability and the Target Lock on the same roll, it is fine. Gunner specifies that it is a new attack.

Alright that's what we ended up ruling just wanted to make sure he didn't run into problems at an upcoming tournament, pretty much impossible to miss your attack

I believe what are are asking is legal.

Han's ability and Target Lock have nothing to do with each other. Both reroll attack dice and you can only re-roll a die once. Of course Han rerolls all the dice while TL only rerolls the ones you want so you could use TL to re-roll some dice and then use Han to re-roll the rest later (all the dice you can reroll has been reduced by the number you already re-rolled).