You are probably doing something incorrectly.
Doubtless.
Here's what I've done. Maybe someone can let me know where I've gone wrong.
1) downloaded installers from Blizzard.
2) Installed 1.12a
3) Upgraded to LOD
4) Put the Classic and Expansion folders from the big bundle in the Diablo II folder.
5) Put the Version Switcher in the Diablo II folder.
6) Started D2 to make sure it was working (A-OK).
7) Opened the Version Switcher.
8) Added a new entry, set to 1.12A Expansion, put the path in (C:\Program Files\Diablo II\Game.exe), and didn't bother with flags.
9) Launched from this entry, and D2 started.
10) Exited D2, added a new entry, set to 1.00. Made sure the isos were mounted in DAEMON tools.
11) Launched from the new entry, watched the files move around, then nothing. No joy.
12) Created another entry, set to 1.07 expansion, launched, watched files move around, then: no joy.
13) Created another entry, set to 1.12 Classic, launched, watched files move around, got a Classic start.
I'm thinking this has something to do with the CD-less versions that I pulled from the internets.
14) Created another entry, set to 1.13c Expansion, launched, watched files move around, got an Expansion start with 1.13 showing.
Pretty sure now it's something in the downloadable, cd-less versions that doesn't really like the old patches, but maybe I'm wrong.
I'm happy to try whatever, but for now I'm way too frustrated and am just going to go to bed. I'll try again after work tomorrow.
Thank you for the program, FB! I hope to get it working, as I've never played most of the old versions.