Oh, I think I know what the issue is now. Midnite♪ must be using Invisibility Mode. When you have Invisibility Mode on, other users can't see you in the online list or when you last signed in but staff can. That must have been what had us confused. Quite a lot of users have Invisibility Mode on; in fact I am using it myself.
I just sent the post again. Thanks!
I just sent the post again. Thanks!