"skull-icon not always visible when player is out" is a newly discovered bug from this thread. So far no details are known for how to reproduce it--what gamemode, for example?--but perhaps if it gets a thread, somebody will figure out some more details.

I tried this with hosting in 6.3 and joining with 6.6a and vice versa, and letting different clients win in different orders and using the /cycle, but sadly I could not replicate this.

I just pushed some code that I believe will fix this in 6.6d, so I'm moving this thread to the Resolved Issues subforum. If anyone encounters it again after 6.6d's release, they can always post in the moved thread and we can move it back into the main issues forum.