If I'm flying Asajj and want to use her ability, do I have to spend a Force if I check range and no ship in range 0-2? Or do I only spend the Force token if I apply the effect?

Short answer: You measure to check eligible targets before you have to spend Force.

Long answer: For abilities like this, you need to go by the order of operation on the card. Asajj states that you can choose 1 enemy ship in your Turret Arc at range 0-2 and spend 1 force. In this case, the range restriction is checked before the other part of the cost, the force charge, is spent. If instead, she were written, "you may spend 1 Force to choose one enemy ship in your turret at range 0-2", then you would have to spend the force in order to be able to measure.

I would also argue that, if you do measure for targets, and you have any valid targets, you have to choose one of them to use her ability on (even if that ship isn't one you really want to target - 4-LOM, for example). It's a bit like taking a target lock - once you start the process, if there is ANY eligible resulting target, you have to select at least one of them.

No because it is a you may choose... Lock is not a you may choose

2 hours ago, emeraldbeacon said:

Short answer: You measure to check eligible targets before you have to spend Force.

58 minutes ago, muribundi said:

No because it is a you may choose... Lock is not a you may choose

Agreed.

Check for targets.
Choose target or Don't pick a target
Spend 1 force or No force is used

10 hours ago, emeraldbeacon said:

I would also argue that, if you do measure for targets, and you have any valid targets, you have to choose one of them to use her ability on (even if that ship isn't one you really want to target - 4-LOM, for example).

Yeah, this makes sense to me. I just wanted to double-check that I won't be screwed out of a Force token by checking to see if a ship is R2 or R3 in engagement.