So i decided hmm i'm going to install the Developer Preview only to find out a week later no matter what i do i can't get D2 running on it.. Everytime it asks me for the CD key even after downloading/installing the Digital Copy and installing 1.13c . I even tried putting my Original LOD disk in the drive "Diablo 2 failed to run. Please make sure your Diablo II Expansion Disc is in your CD-ROM drive, then click on 'Retry'." Anyone else find any workarounds for this OS? Played with every compatibility mode and all with no luck.
My friend had the same exact problem, I thought it was just his OS install acting weird though. However, if I recall right, my D2 worked fine on WDP, so idk (mine installed from the battle.net installers)
I think D2's just about done for. From what I saw, my brother had to run it in windowed mode for both 7 and vista. It's understandable that it doesn't work anymore.
Try a Glide Wrapper, such as a OpenGL to Glide wrapper, or a DirectX 9 to Glide (I recommend nGlide) Wrapper. Pretty much the only ways I can think of to play D2 reasonably on OS's above XP without color corruption or FPS issues (or, in your brothers case, the need to run in Windowed mode).