Although corruption could have occurred I doubt it as you should have received a report that something failed during the upgrade process if that occurred. All workflow should be fully supported in the newer version from previous versions.
I would guess that you have fields that you desire (they may be custom fields) that are not showing correctly when you are creating a new test or editing an existing within the details section. I would need to see the situation first hand, but my guess would be the following may be occurring...either your project is no longer associated with the template that this workflow was created under (if using templates), or if not that it is possible that the your group membership may be off (you may be the member of more than one group) and it isn't picking up the desired group first for displaying the fields ordering and displaying. These would just be possible guesses based on what I have seen in the past, but without seeing these firsthand and the workflow involved, I can't say exactly what is happening.
Hope this helps and if not I would open a support case with your ALM support group to address it,