Q. I use my forums in the root directory, how can i also use vBadvanced?
A.
Step 1
Rename vB's default index.php to forums.php or forum.php or ANYTHING.php
Step 2
Login to your Admin CP and go to vBulletin Options > Forums Home Page Options > Script Name for Forum Home Page
Change this to match what you called your default vBulletin index file. Do not include the .php extension though as it's not nessary.
Save the options.
Step 3
You may now comment out or remove the chdir line in your cmps_index.php file as it's no longer nessary. Rename the file to index.php, upload it to your server, and you're done.