I have the Application Performance Monitor looking at the Orion Server (via SNMP) and its shows the "SW Orion Custom MIB Poller" (OrionCustomPollingService.exe) down. I did a search on the Solarwinds server for this file but it was not found. Is this file necessary and is there something that needs to still get installed?
That Template was based on Orion NPM 8.5.1, which did, in fact, include a Custom MIB Poller. NPM 9.0 dropped that service and added a couple of others. You should modify your template to reflect the change in services. When APM 2.0 ships, we'll ship an updated template.