I just upgraded from URT 2.0 and I can not delete lots when I had the permissions to do so.
We have added new permissions (one of them being the ability to delete lab/lot/test) to URT 2.0. We do not give new permissions to users when we do an upgrade.
To add this new permission, go to: Tools, Security, Administrator and add the permission to the user.
If you require further assistance please call Bio-Rad Software Support at 800-854-6737 option 3.