After the OTA update, I waited a few weeks and then found the one click method to re-root. I downloaded the latest driver from moto, and the one-click program. Installed the driver, unzipped the one-click package, started the .exe and hooked plugged in my X2 when it told me to. The X2 was set to usb debugging only before it was plugged in and I selected charge only like it said to. The program ran, said it was a success, but when I try to run a root check it tells me I am not rooted. Hope this helps.
Initially, I thought it might be because SU was already installed from the previous root, but I'm not sure and have found no easy was to uninstall SU. i.e. there's no uninstall option with the program.
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