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You can try using EasyFlasher in APX mode to flash back to stock.
Use this guide to get you started: Frederuco's Guide to Root and ROM the TF101
Once you get EasyFlasher open, instead of flashing recovery use the flash stock firmware button. You will have to grab the latest firmware for your tablet from the Asus support site: ASUSTeK Computer Inc. -Support- Drivers and Download Eee Pad Transformer TF101