I used the manual root w/ZERG and received the OTA for .902, which broke root. The exploit in the link you posted does work, awesome!
No... just put the zip file on the desktop of your windows PC. Extract the file there. Then simply execute the run (batch) file. Make sure you have your phone connected and the latest moto drivers USB and PC Charging Drivers - Motorola Mobility, Inc. USA , and set your phone's USB connection to "Charge Only".
Will this allow you to stay on the upgrade path?