Default [Q] Return to stock issue

I am selling my TF700 and wanted to return to stock before selling it(currently have chromi-x 5.3). I downloaded the 4.2.1 stock rom from the Asus website, unzipped, copied the rom zip to the sd card of the tablet. Rebooted to TWRP and installed the zip. Everything seemed to install fine. The tablet rebooted and the lock screen came up. But when I swipe to unlock, I get a 'Unfortunately, Launcher has stopped' message. I can hit Ok, but the message just keeps repeating. Any help would be greatly appreciated.