Hi Irv and welcome to the forum!
Sorry for my late reply here. This can be easy or a lot of work I think we have two choices:
1. connect the cameras directly to NCS which probably is the easiest way,
2. connect the NVR to NCS.
On the website they talk a lot about ONVIF which is a standard on how to connect cameras and NCS. First I would recommend you to download the latest version of CNS 220.127.116.11 from here http://community.netcamstudio.com/t/netcam-studio-1-4-1-netcam-studio-2-0-beta/1799 That version have among other things improved ONVIF.
I don´t know if the cameras support onvif, but the easy way is to test. In NCS add the cameras using the onvif tab. When you search for the cameras they should appear if they support onvif. If they do not appear the cameras must be added using the tab Custom URL. Then we need to find the Address which is rtsp://username:password@ipnumber:554/xxxxxxxxx The million dollar question is what is xxxxxx
The second alternative above is to connect the NVR to NCS. The process is the same as for a single camera. If that do not work a lot more information is needed.
We start with the easy way first