Evidently, part of Revo's routine is to start the targeted program's uninstall file. When that happened, the same error came up as when I did it (must have SP2 installed). Revo then continued with its remaining steps without incident. Then when I checked how effectively it had removed everything, only the listing for Studio 10 in the Add/Remove list was gone. The Studio 10 folder is still in Program Files, and that folder has at least 10 folders, many of which have multiple subfolders. There are also several executable files in the Studi0 10 folder. When I did a registry check, literally hundreds of entries had references to Studio 10.
I tried to manually delete all those folders, but I received an error message about one dll that could not be deleted, and the deletion was aborted. Just this morning I tried to delete all those folders and files again, and it worked. I don't know, maybe I have screwed something up that will raise its ugly head later?