I've finally started working on this and I'm trying with v.12.5.0, since v.11 is now an old version and trial keys are generated for v.12 only.
I think I'm in the right place where you create a media set and then rebuild, but when I select the old catalog file to be rebuilt it says, "Not enough disk space to duplicate file." I don't know why it would be duplicating the file on that drive. I'm unable to move/copy my two catalogs to another drive due to them being large; I'm running into disk error -36 before I can complete it.
Jeremy