I believe WoW classic uses a different .exe name (wowclassic.exe vs. wow.exe), so vorpX can’t recognize it. I had originally planned to check the classic version before 20.1.0, but ran out of time. Will happen early next year.
For now you can try this (no guarantee that it works though):
Either:
Rename your wowclassic.exe to wow.exe and see whether that works.
Or:
1. Open the “Local Profiles” page in the vorpX config app.
2. Make a copy of the WoW profile, keep special shaders.
3. Assign wowclassic.exe to the newly created profile.
WoW has to be run with the graphics API set to “D3D11 Legacy”, otherwise 3D definitely doesn’t work. For the normal WoW vorpX handles that automatically, for your custom classic profile you would have to do it yourself.
If the above works, it would be great if you could share your profile for others in the vorpX cloud, ideally including the “D3D11 Legacy” hint in the description.