Thanks Les. I just succeeded in dd'ing (Genesis method) my WD 80GB drive, and now it will work with 3.92. I thought I had tried that before, but either I didn't or I used a different original DMS as the seed than the one I used this time (which is an original Kenwood 10GB DMS).
The same action did NOT seem to work for either a Hitachi 120GB or a Samsung 160GB. Unfortunate, of course, as I use the larger drive for my music.
So, unless someone suggests otherwise, based on your info, posts from other users experiencing problems and my own experience, I conclude:
PMM 3.92 works with hacked Seagate and Western Digitial drives, though it may be necessary to copy the signature from an original DMS.
PMM 3.92 does NOT work with hacked Hitachi or Samsung drives, whether or not an original DMS signature has been copied to the new DMS.
Therefore, my next step, which I was considering anyway, is to get a WD 250GB drive, and cross my fingers. (I don't know what I'm going to do with all these extra 2.5 inch drives.)