The way this works is it will reboot your device into fastboot, boot a kernel, inject root and SuperSU(available on Android Market), set permissions, test itself and let you know if it passed or failed.
CASUAL also provides an unroot option to remove root permissions. This can also be done from within SuperSu.
CASUAL stands for Cross-platform ADB Scripting, Univeral Android Loader. CASUAL jar files are a wrapper for the CASUAL scripting language. CASUAL allows rapid and accurate deployment of hacks and exploits. CASUAL allows for automatic updating of its scripts via pushes to the SVN server at android-casual.googlecode.com. While I expect no problems at all, if at any time a serious problem is detected with the script, i can flip a kill switch to shut CASUAL downand you will be brought to a support page.... most likely here. This is intended to add a level of security so that you know this will be safe.
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