I actually did change the network software after I upgraded to 7.5.5. The Internet connection was not working from the outset, and I was thinking that when I upgraded to 7.5.5, that might fix it (fat chance) or I would get some more hints about how to get it done.
It should work with MacTCP also, but setting up MacTCP properly is more complicated than using Open Transport with TCP/IP.
In the meantime, I am having problems with my USB floppy disk drive. Mac OS X Lion will not show many of my old 68K floppy disks on the desktop, so I cannot get images of them. I can see all sorts of other floppy disks that have files on them, both Mac an Windows disks, but many of the original purchased floppies that I have, such as Wizardry and Write Now do not show up.
Could it be that the floppies that do not show up are in the older (Mac specific) 400k or 800k format? You cannot read them using a USB floppy drive. They are in a special format that requires a drive and related drivers that can write and read with variable speed. That is how Apple managed to get 400KB and 800KB on 360k(SD) and 720k(DD) floppies. Those floppies can only be read in a (old) Mac with built-in Mac floppy drive. So, find someone who has such a machine. Disk images made of those floppies can be used with BasiliskII. (There seems to be a way to access those floppies in Windows with special software, but I do not know details.)