This is my problem. I'm wondering if winimage under Win7 isn't working. Is there any way to tell (on the Nook itself, perhaps) if the root actually worked? The CDC composite device only shows up under the Device Manager if the MiniSD card is inserted and the NC booted from it. When it boots after the SD card is removed, the Nook shows up under devices with two B&N Ebook Disk USB Devices (the internal storage and the MiniSD card, I presume) and a USB Mass Storage Device.
EDIT: As a further note, I installed ADB and can get ADB Devices to return nothing in the command prompt, and have a .android folder in my User Profile ... but no adb_usb.ini.
Ok well. I was finally able to get it to work. I have to plug my nook into a different computer (also win7) and Nook showed up in device manager. Not sure why it wouldn't on my laptop.