vSZ cannot migrate ZD3k after updating to v10.2.1.0.75
I am running vSZ version 18.104.22.168.496 and trying to use the ZD Migration Tool to migrate from a ZD3k. When the ZD was on 10.1.2.0.120 I was getting a strange tftp error after selecting AP's to migrate, and the process would fail. After a lot of troubleshooting I decided to move one of our ZDs to the latest version hoping that might clear it up. Ever since moving the ZD to 10.2.1.0.75 the vSZ fails the migration instantly with a network error:
Can't connect to ZoneDirector. Please check IP, User name, Password and make sure ZoneDirector is reachable.
I have other ZDs that are still on 10.1.2.0.120 and the vSZ has no problem connecting to them during the migration process. It only seems to be affecting ZDs on 10.2.1.0.75. The ZD can ping the vSZ's control interface, and vice versa. We are trying to proof-of-concept this process for our upcoming vSZ deployment but so far we have not been able to perform a single successful migration.
Is this a known issue? It's worth mentioning that the vSZ is a 90-day evaluation. Is the migration process supported on an eval?