As the title describes. Hitting 'pass turn' while a unit is moving causes the unit to get stuck between tiles and the tactical battle becomes locked.
I haven't tested other instances of this, so here's what definitely works on my build.
Conditions for reproduction:
Entered a 1v1 tactical battle; My sovereign against one wolf. Clicked to begin moving two squares forward. Hit Pass Turn during the movement. Sovereign freezes in between tiles with leftover action points. Cannot initiate any other actons -- Attempting to move again or cast a spell fails. My only option was to hit auto-resolve to exit the combat. I performed this 3 times, producing the bug each time.