After painstaking effort (If I never see another PIDL it'll be too soon)... I have bent the MSN shell extension to my will!
Edit: Just noticed this was my 100th post. Fancy, that. Oh and don't worry, I have much prettier/more useful plans for this application given its new abilities. I've also fixed some bugs in the shortcut creation routine (even what I posted the other day still has a ~100 character query limit).