if you r rooted from device browser go here:
adbWireless.apk - 4shared.com - online file sharing and storage - download
it should install then u can use adb without cable so you should be able to install your market
I am having the same problems with ADB. I am on a rooted stock nook now and have set up sdcards for froyo and HC to boot from cards. I can get them to boot but cannot get the gapps on. I read the post about the wireless and would assume that would only work if you were flashing froyo/HC to the rom. Anybody have any suggestions on how to get the gapps on the sd card?
Several options, the easiest of which is to take out the micro sd card, put it into a standard sd card adapter and push it into a computer that has a card reader, and simply place gapps on the sd card that way.
Another option, which I think should work for 99% of those out there, is to follow this link to get the correct drivers installed on your computer.