• GSN is using Flex as a CPV product, whereby a user opts in to get a reward after watching at least 5 seconds of the ad. The Web 1.8 template has been modified to allow this feature. 
  

• Flex CPV is designed to run with the same socialVars as a Views ad, with the addition of a new "cpvOn" variable that should have a value of "true". If cpvOn is undefined or set to false, Flex will render normally. 
  

• Publisher calls loadMediaBrix() to prefetch a Flex CPV ad
• Flex CPV calls the adVerification callback to display the tickler
• At the end of the 5 second countdown, Flex CPV fires the rewardConfirmation callback and displays the close button.
• On closing the ad, Flex CPV fires the adClosed callback

• Test harness: https://apps.facebook.com/mediabrix/test/lee/flex_cpv/viewer.html
• Test ad unit: Web1.8_SocialFlex_VAST
• Select the desired product type from the drop down then click Load Ad Unit.
• When switching between SocialFlex CPV and SocialFlex, you must refresh the browser window.