As of now the error/warning messages provides are very unuseable.
While technical information and IDs are provided, the is no info about a possible cause of the error or solution pathways.
I would like to see possible explanations for error and warning either in the migration portal itself or at least in the according confluence space.
Error: User not found - Migration not possible
I wounderd why this is a migration breaking problem although roles are not even part of the migration.
I’ve found the problem beeing the project leader not being available in the target instance to be the problem and I expected at least a hint on such a problem either in the error message or at least in your confluence.