Hello Wayne from Wellington New Zealand.

I have the same loss of DMR Master connection when using DMR Plus IPSC2.
It stays connected for some hours or days but sometimes disappears from my DVS dashboard.
I use the DVSM [* & 0] function to establish it again.
Funny thing is that it appears to still put traffic to the New Zealand IPSC2 server even though
the dashboard says it's not connected.
NXDN, D-Star and YSF do not go missing except for an internet "blip" when I sometimes
need to reconnect all of them.
DVS is such excellent software and if drop of DMR Master is the only thing wrong then I live with it.
There might be a fix sometime or it's caused by bad net from time to time and nothing to do with DVS.
Here is my dashboard: http://zl2tws-dvs.ddns.net

Best 73 and good DV to all. John ZL2TWS