It seems to me that you are not starting from 1.0.7, hence all the inconsitencies with the database you are having.
About testing the migration, what I usually do is to replicate ALL the system to another server (we're using virtualization), and test that with a different ip, once the upgrade process has gone flawlessly, I then to the upgrade to the real server.
Hi, when I mean rollback I roll back with rsync to my last backup. Before any changes. At present I have a fully working 1.0.7 ISPCP system. If I launch the migrations scripts from the IMSCP RC3 I get the database error as posted above. I'm currently building a test VM system but the problem is with my stable production system. I can't advance What can I do as I really want to migrate ....