Hi GREGD,
Doublecheck if you have the following ports open between SnapCenter Server and SAP-Host:
TCP_22
TCP_8145
TCP_8146
This ports need to be open in both directions.
Have you added a SAP-Host "RunAs" User at Snapcenter side? This User needs to have administrator privs.
I've just a Linux-based "Clients" at my environment but hardly know how tricky the port's issue is.