The softroot includes the Trook app, right? I think Trook can install packages for you.
You'll need to download the apk file from here:
http://nookdevs.googlecode.com/files/nookMarket.apk
Then plug your nook's USB cable into your PC. Open the nook folder. In there, create a folder called "my packages", if it doesn't already exist. Drop nookMarket.apk into the "my packages" folder on your nook.
I can't remember the exact details, but if you play around with Trook, I think you should be able to install the package now.
I hope this works; I'm going from memory, and could be wrong.