Glad that worked out. I had a look through the 3DO SDK disks too (as the dev machines were connected to nubus Macs over a FDDI connection) but didn't see anything useful. There's a driver for the nubus board but I couldn't see any FDDI-related resources in it.

Update:

Actually it would probably help if I had a drvr template for ResEdit. As you have one, maybe there is something of use in the 3DO driver. Here's one: