Unicorn666
Skeletron Prime
The enemy's disappearance is tModLoader's problem, not the mod's. I belive, it was fixed? Dunno really.I don't see an update? Does it take some time to upload it to the mod browser? For me it still shows no update.
Also: did this fix also fix the enemies disappearing? That is a difficult issue to deal with as well.
Try updating manually, not via the mod browser.