When collecting Agentless inventories, there is no "shipping off" since there is no agent involved. The inventory solution uses PPA and Credential Manager to connect to a machine via the network and collect the data desired. Since it looks like you are specifically collecting SNMP data, you may want to use SNMPWalk to determine if that data is collecting from the resource. With that tool, you can run a command similar to the one below to see if that OID is functioning as expected:
“snmpwalk -v:2c -c:<community string> 10.31.15.29 <OID>”
As for the Test button...yes, there is a known issue preventing that from opening the test window. This will be resolved in 7.5.