Hello Karl!

"Unexpected BLOBs" are usually nothing to worry about - especially when planning a migration: those are files that have been left over after the appropriate item has been deleted, so unless you find a lot entries those can safely be ignored...

About the "No such account" error, I definitely need a bit of context
Can you please compress the logfile you mentioned and send it to community@zextras.com?

Have a nice day,
Cine
the ZeXtras Team