Damian, Milkyway (which is working) is using Centos 6 Andromeda is using Centos 7 and TheCosmos uses a raspberry pi 2, so Raspbian
Interesting. Maybe that platform has a subtly different format than what I expect. Mind running the following for an arbitrary process and telling me the output?
ps -p <pid> -o etime
Nyx uses /proc to get this information too but that's platform specific, so ps is used as the more universal fallback.
From MilkyWay:
[root@clutterbuck ~]# ps -p 23780 -o etime ELAPSED 78-14:14:25
From Andromeda:
[root@vps110165 ~]# ps -p 972 -o etime ELAPSED 19-07:43:36
From TheCosmos:
root@Tardis ~ # ps -p 20717 -o etime ELAPSED 10-06:23:19
Hope that helps.
Alan