Still busy in real life alas, hence I didn't see your request to check the discs until today... but it seems your magnificence wouldn't halt for even a day. Once more, my heartfelt thanks!
Regarding Ultima V, it had no copy protection on the discs, but as you have discovered it had an unusual file system (duffer speak ahoy!); all I originally did was do an X-Copy of the data disc that came with the original, and play from that instead. As there is no option to make a save disc from blank floppy, I'm assuming that any 2 disc .adf set for Ultima V will be of the same structure, with a set area for the saved games.