Hi, sorry, I didn't make myself clear ... With 2.1/4.1. in order to format MFS 800K disks, you MUST use Resedit to delete all but the ".Sony" driver and "Dispatch Kernel" resource on the HD20 INIT. (I believe the HD20 INIT "TFS" resource has all of the HFS information).

As for your experiment with the HD20, I did want you to use the 2.1/4.1 configuration to see if that worked with your HD20 hard disk unaltered. If that worked then it meant that the Finder was irrelevant to starting up with your HD20, then you could experiment with the modified HD20 INIT.

I am quite surprised that 2.1/5.0 did not work with your HD20 since it is absolutely supposed to. There were two different drivers 1.0 & 1.1 and it's possible that your drive somehow needs the 1.1 driver and possibly System 3.2/5.3 with which it was released (or at least more resources than 2.1/5.0 has) if that is a factor in how your HD20 was formatted.

As for System 2.0.1, I've never heard of such a thing. AFAIK, 2.0 went directly to 2.1.

So maybe that Gamba file is somehow modified ....

This now makes me curious about using the modified HD20 INIT with System 3.x/Finder 5.x configurations. I'll look at the differences between Finder 4.1 and 5.0 as well. Also, since System 2.0 & 2.1 are minimally different, I'll look at 2.1 vs. 3.0 as well to see what happens with 2.1 & 5.x finders with the modified HD20 INIT ...