Compatibility with other mods
This page contains info about compatibility with other D2 mods, and workarounds for getting D2DX to work with them.
If you have installed PlugY in a separate folder and launch it like:
"D:\Games\Diablo II\Mod PlugY\PlugY.exe" -3dfx
You may encounter the following error:
To resolve this, copy the D2DX glide3x.dll into the PlugY install folder as well ("Mod PlugY" in the above example).
Try passing -dxnoresmod to disable the built-in resolution mod in D2DX. This still allows MedianXL to use 1024x768.
D2DX can generally be used with PD2 by replacing the glide3x.dll, however the PD2 launcher can not be used (it restores the files).
Delete the D2HD.DLL in the D2 folder.
It seems that PD2 needs to whitelist D2DX for use on their MP servers. You could ask them (nicely). :)