Make the video
Two steps: make it, then save it. It's made here, on this computer, from exactly what you saw in the preview, and nothing is saved until you choose where it goes. How long making takes depends on the computer, so once it starts it'll say how long is left. Keep this window open and in front while it works: a browser slows down a page it can't see.
Reading your setup…
Making a video lets us know your company and team name, so we can see who's using this. That's all. Privacy
Your setup is one file with everything you chose: the brand and logo, the list of people, the music and your preview changes. Next month, load it on the brand page and start where you left off. It has your team's names and start dates in it, so keep it somewhere private. Photos, and a song file of your own, aren't in it.