Thanks to hrb264 for reporting this one on Discord.
The replay is for the DoveLems level Maze in a Clepsydra, but the glitch will happen wherever this precise setup occurs:
A lemming is walking across a platform <=2px in height.
The platform has a OWW facing the opposite direction of the walking lemming.
The walking lemming is assigned a Miner.
Expected outcome:
No terrain is destroyed. The lemming stops mining and turns to walk back the way they came (i.e. facing in the same direction as the OWW)
Actual outcome:
No terrain is destroyed, but the lemming completes a full miner swing and steps through the <=2px platform, falling through the other side. They remain facing in the same direction (i.e. the opposite direction to the OWW).
Possible cause:
Best guess is that the miner detects the OWW too late, and has completed a swing (during which their Y position is increased) before they react to it. We need to detect the OWW earlier and adjust the miner's journey appropriately.
Fixed in RLPlayer commit 5a26622.
This is a physics update and could break existing replays, but only if they specifically involve turning a Miner on a OWW.
In addition to the above, another similar bug has had to be addressed. I've posted here (https://www.lemmingsforums.net/index.php?msg=105689) regarding this one.