The "Manual Configuration" page outlines manual setup you may need to perform after the secure restore to the target gateway was done:

• Non-mgmt network interfaces should be still disconnected at the target gateway.
  To enable applicative traffic on the target gateway, please configure the source gateway's and/or target gateway's network interfaces in a way that will not cause IP address collisions.

• If the source gateway was part of an API-Connect gateway cluster, you might need to make API-Connect aware of the migration by removing the gateway from the cluster and adding it back again.

• If the source appliance is an X1 appliance and the target appliance is an X3 appliance then revert the source IDG appliance firmware level back to its original firmware level it had before upgrading to the migration only 10.5.0+ firmware build you obtained from the DataPower support team, to make it usable again.