The best place to start if you need help with a specific product is to contact the developer. All WHMCS Marketplace developers have both a website and support URL listed.
1.0 First Release
Free live chat App
Chat and Engage with Your Customers to Increase Conversions!
A premium live chat and help desk software for customer service and online sales.
PreMadeKB - Readymade Knowlegebase Articles for WHMCS - With Images and 269+ Articles on cPanel, Softaculous, etc.
Add a "Video Tutorials" section to your WHMCS menu, with your own Video Tutorials.