I'm late to the party on this one, but I'd have to echo the sentiments already expressed here.
We use NMC to manage 12 Networker server, the largest with around 900 clients.
The Jobsdb is set to keep 3 days and 120Mb of history, but it can be half an hour before we get any response on a bad day. We also suffer the hangs and crashes (7.4.4 at the moment)
It's got so bad that we've found ways to get Nwadmin working on the (Solaris) backup servers, so we can still work.
NMC is potentially a great product -it's abilities are far beyond what Nwadmin can do. However, our staff have to be prodded into using it due to the ongoing issues.
Just my 10p (I'm in the UK ) -worth.
I am in the same situation with NMC,how did you get NWADMIN to work, I always liked that GUI, I use nsrwatch just so I can see what is running when I come in the morning.
It is not unsupported at all; it has been shared several times by EMC as well. One just have to remember that it should be used for monitoring only and no edit or operational tasks.