In the current download of the styles from the NL website, namida_machine has custom lemming sprites. None of my styles are meant to have custom lemming sprites, so I can only assume this either got applied to the wrong style, or was a user modification that accidentally got included in the download.
Aside from that, L2 Shadow, L2 Highland and Arty Underwater also have custom lemming sprites in the current download; but these might be intentional. (Arty Silhouette and Xmas also have them, but I *know* it's intentional in those cases.)
This bug is something on Nessy's side: namida_machine, l2_shadow and l2_highland do not have custom sprites in the NeoLemmix repository and neither have the zip files on my dropbox account (i.e. the files that you get when clicking on a direct download here on the forums).
The custom lemmings sprites in Arty's Underwater style are intended and should be kept.
It seems that this was indeed a user modification that accidentally got included in the download. I have no idea how those sprites got into the main repository in the first place since I keep it separate from my own styles repository, but now that I know it's something on my side I'm going to remove them immediately. Those sprites (especially the Machine ones) are fan-made, optional add-ons made for fun and shouldn't be standard.
Everything is fixed now :thumbsup: