On 10-13-16_564425c, trying to play the Lemmings Redux pack (using the experimental because a feature I use frequently is bugged in the stable), I got to Keep Your Hair on Mr. Lemmings and noticed that I could not assign any skills to lemmings slightly left of the entrance.
I tried highlighting lemmings and assigning skills that way, but that didn't work either - anywhere. Not sure if the ability to right click a skill to make the highlighted lemming perform it was culled or if it's also a bug - it did work in the stable, though.
I have not determined what about this level causes this behavior. I'll add more if I figure it out.
