Hello,
I'm running Ubuntu 14.04.
The tray icon for encode server seems missing in 2.6.3
Maybe OS related - although 2.6.2 was running fine.
So as I did not see any tray icon, I've twice started encode
server and then ↓

There were two processus in monitor system for dcp-o-matic encode
server.
Another little problem I forget to mention since some versions
now, with auto-update : it launches firefox - right - but with
message error "firefox is already running". That does not prevent
from working.
Gerald.