Was having trouble with Advanced Text Widget working (among others) in 3.6.7 and read about the patch to the function.php. I downloaded and installed and lost my website completely! That wasn't a patch, it was a hand grenade. Had to reinstall 3.6.7. function.php to get things back. The old file is much larger than the patch file. What is wrong with this scenario? Must all patchs be installed for one to work? Sounds pretty scary to me. Any advice is appreciated.

Did you unzip it before uploading it to your site?