If I attack a smuggler figure with Vinto, such as a Weequay, the Weequay plays On the Lam and moves out of my line of sight, do I still get to resolve Boltslinger?

I don't believe so as the attack is aborted before it could be resolved.

The attack misses, and you resolve any after attack resolves abilities as normal (see a1bert's response below)

Yes. The attack misses , but you resolve it fully. Thus all applicable "after attack resolves" and "after you resolve an attack" abilities are available.

(The attack does not abort, the new rules say it misses if the target is no longer in line of sight - due to the target or attacker moving or another figure moving to block line of sight.)

ATTACKS

· During an attack, if a figure ends its movement such that the
attacker no longer has line of sight to the target, the attack
misses.

That's what I get for answering a rules question late at night.

Totally forgot that section in the rules.