I try to get my older Cubase SX 3 working in Windows 8.
All works fine, but I seem to need an upgrade for the VSTDX.DLL file to version 3.37
Steinberg did offer this download in the past, but I can’t find it anymore.
Many versions 3.3.09 and 3.3.10 can be found and are included in the SX updates still available.
Version 3.37 would avoid the “Direct-X Wrapper: Plugin Not Loaded” error.
the rest of SX 3 is working ok with windows 8.