The following error occurs during migration process:
Deployer has been terminated by exception: Line 546 Position 4 Error: The element 'migration-dump' has invalid child element 'role'.
This error occurs, when the migration is performed with "Skip server global settings and system services configuration" option enabled, or when selective migration is performed without server settings.
This is Plesk internal issue with internal ID PPPM-2680, which has been fixed in Plesk 12.0 microupdate #40.
Apply the latest Plesk microupdates.