No fault of your own, but you shouldn't have been assigned to that task without adequate training and completed a competency check. The first 10 (or so) hours after the competency check should be under supervision, prior to being released solo. You were thrown in the deep end here, the 204/05/12 is a difficult platform for long-lining. All things considered you were lucky, obviously helped out by enough skill to pull it off, just.