I have spend many hours (days) on trying to get access into this thing with no success. If we can get to the boot loader maybe we can do what was done on the Sony X10 and load a custom rom on top. I will look into this but don't think it will work since we would still need adb access in order to load the files needed.
We need some better developers then me to look into this tablet to see if access is even possible.
Tablet: Asus Transformer TF300T
ROM: CM 10.2 (Nightly)
Phone: Motorola Moto G
ROM: Stock Android 4.3