Open up the N360 interface.
Select the "Settings" tab.
Select "Antivirus" from the Detailed Settings field.
Under the "Scans and Risks" tab, scroll down to the bottom
Locate the "Exclusions / Low Risks" section
Next to "Items to Exclude from Auto-Protect, SONAR...etc" click on "Configure [+]"
A window should pop up labeled "Real Time Exclusions"
Click "Add" and browse for your folder. Don't select a specific file, just select the entire folder.
Be sure to check the box for "Include subfolders"
Click "OK"
Click "Apply"