Player1 advances the ball into the front court and pulls up seeing Player2 (his point guard) slightly trailing. Player1 lobs a leading pass, still in the front court to Player2. Player2, still in backcourt when pass leaves Player1, leaps across mid court and recieves pass while airborn in front court but before landing in frontcourt. BALL clearly stays frontcourt. Is there a violation ?

Violation. A2's status is established by his point of take-off. Ball's status is established by hitting his hand. violation.

Until A2 touches the floor in the FC, he is in the BC. If he touches the ball prior to landing, it's a violation. It has nothing to do with whether the ball ever left the FC or not.

Same play, except A2 jumps from OOB. Is it a violation if A2 touches the ball before he touches it inbounds?

Yes, it is.

You are where you were til you get where you're going.