In the following level, I am only able to assign 1 floater; the other 4 lems fall to their deaths.
I tried opening the level in the editor, and if I separate them out by 1 pixel, I can assign all 5.
Proxima reported that the level works fine in 12.10, so I'm wondering if it may be a 12.11 thing.
Does priority invert have any effect? Does this also occur if they are non-preplaced lemmings stacked Compression Method 1 style?
Ah - I think I know why this is happening, and if I'm right, it is indeed specific to preplaced lemmings that start on the same spot (whether or not they're still on it at the time of assignment). I'll sort out a fix tomorrow.
Fixed, and will have a 12.11.2 update for this up shortly.