I've just discovered something weird about the MiniMg V, so I can see why you're asking how. I'm sure I remember deleting a sub-bank, but I've just tried doing it and I can't find out how it's done. It's three o'clock in the morning here right now, though, so I'll have another look tomorrow.
If my memory is at fault and the sub-bank can't be deleted, the best option would be to copy the other patches to a new sub-bank and just avoid ever opening the one with the problem patch in it. If you never open that sub-bank you won't be likely to bring up the problem patch by mistake.
Open the sub-bank with the problem patch in it. Bring up the first patch. Click on `save as' and create a new sub-bank to save the patch into, in just the same way you'd do if you'd created an entirely new patch and you wanted to save it in a new sub-bank. Then go to the problem sub-bank again, and bring up the second patch, saving it to the new sub-bank, and so on with the third etc. Make sure, of course, that you avoid selecting the problem patch.
It'll be tedious if you have a lot of patches in that sub-bank, but at least you won't lose any patches and you can avoid ever opening the sub-bank with the problem patch.
You can click on the name of the sub-bank and rename it with something that tells you never to open it.
Regarding the first suggestion, of reinstalling and removing your problem patch before restoring your own patches -
that depends on whether your sub-banks are automatically restored when you install the software again, as I mentioned before. It also depends on how you did your backup, whether by individual patch or by sub-bank.
If you backed up the entire sub-bank in one go, you won't be able to delete the individual file.
If you saved the individual patches you'd presumably be able to identify the problem patch by the patch-name if you look at your backup using whichever kind of browser you use.
If I can work out how to delete a sub-bank I'll post the method later.
