Maybe my original instructions were in the wrong order? Specifically the application of 1.10 and the application of HU 1.2. This is just a shot in the dark, but maybe try this: delete the Hell Unleashed folder (the copy of your D2 folder), re-copy your Diablo 2 folder, apply the 1.10 patch to the copy, then extract all the HU 1.2 files to the copy. Again, be sure to run D2ModSetup and launch from Hell Unleashed.bat.

Do you see the command windows when you launch? And does one repeatedly say "cannot connect to server?"