ToME: the Tales of Maj'Eyal

1) Does the Gesture of Pain interact somehow with Psiblades?
2) What does "You cannot cancel this talent once the first bolt is cast" mean (Cursed Bolt description)? Does it mean that everytime a shadow and an enemy is in range i'll use my turns to mind-blast the enemy with my shadow (for ever?)?

Some of the gestures talents interact with psiblades, but not pain.

It means you can't press esc. To cancel targeting. Once you fire one you have to fire them all.

some talents fire multiple projectiles at once. so, as Micbran said, all or nothing. can chose just some.

Rather, you CAN cancel subsequential bolts (they will not be fired), but the talent as whole will not be cancelled (will consume time and cooldown).