Thank you for your interest our producs.
Kindly visit this thread to refer how to edit the intro page http://forum.enginethemes.com/thread/customize-intro-page-template/
In QAENGINE intro page, allow Admin to add morethan 1 image for the site introduction to the user’s. Slideshow is very important or allow automatic image changing time by time.
Also a minutes Mp4 video background if added will be awesome.
To implement that feature, it requires coding skill and WordPress skill. It should be better if you contact to a freelancer to do it.