I discovered that I needed a registered version of Miamidx to make Genesis work
That's nonsense. You need a MiamiDx keyfile to get a full version of MiamiDx or you need a Genesis keyfile to get the full version of Genesis. There is no need for MiamiDx for Genesis or vice versa.
You can go online with the demo version of any TCP stack you like (Miami, MiamiDx, Genesis, AmiTCP, TermiteTCP etc.) as long as you don't need ADSL features. ADSL only works with the full version of MiamiDx.
As for the CD-ROM check the CD0 file in Devs/DosDrivers if it points to the correct Device and Unit.
As for ENV, copy the original Startup-Sequence from your original Workbench disk and never again edit it. As a more advanced user you might search the Assign ENV: RAM:ENV command and check that no command which is earlier in Startup-Sequence than that tries to access environment variables.
Bye,
Thomas
