I'm not sure/ it depends on what you are asking.
A)If you want to load a dvb on AutoCad-startup then you can simple use the built in 'Startup Suite'.
(type
appload) in commandline and look for the briefcase "Contents"-button. There you'll be able to select which lsp, arx,vlx or dvb's you want loaded.
Use that.
B)However if you want to load the stray bit of VBA-code from .Net then I use a somewhat dirty way. (I'm not sure if there is a more decent way of doing this)
Dim acDoc As Document = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument
acDoc.SendStringToExecute("-vbarun //ServerOrDrive/folder/subfolder -yourProject.dvb!yourModule.yourMethod ", True, False, False)
What this does is 1) load the dvb and 2) run the method called.
However if you only want the *dvb loaded i guess you could make a dummy method and call that.
I'm sure as rain not saying this is 'how it's done' but it is quick and dirty, it does work.
Note that running vba like this (or in either way as far as I know) does not run in sync/thread with your .Net