Hello Drew,
1. No it does not, the design of the CrowdCompass app differs from the design of the Event website, things like admissions items, sessions, descriptions will come through into crowd compass.
This article will go more in depth on the integration between CrowdCompass and Cvent:
https://support.cvent.com/apex/CommunityArticle?id=000009555&Lang=en_US&searchTerm=sync%20to%20crowdcompass2. This is subjective, youtube probable has the best servers to since google's infrastructure is huge, vimeo is also a great option, both vimeo and youtube will have better server infrastructure than most video hosts.
3. Yes you can use
YouTube, Vimeo, or Wistia:
https://support.cvent.com/apex/CommunityArticle?id=000068241&Lang=en_US&searchTerm=video
4. No, you cannot have a video as your hero background------------------------------
Gurgen Grigoryan
Web Developer and Content Manager
The Regents of the University of Michigan(Office of Development)
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