If you score a hold point from Sigil of the Storm at the start of your turn, then lose control of it and retake it during the same turn, do you have to cycle a rune (does the conquer trigger)?

Ruling: No, you do not have to cycle a rune. To conquer a battlefield, you must gain control of a battlefield you haven't scored yet on that same turn. Since you already scored Sigil of the Storm on a hold at the beginning of your turn, you cannot conquer it on that same turn, so the conquer trigger does not occur.