Hi guys
I've recently moved across from OBS and I'm struggling to understand the different setup with vmix as I'm used to having "Scenes".
I currently run a church broadcast for our Sunday services, with a very basic configuration, 1 x web cam (soon to be a Canon E200 SL2 SLR) with a Avermedia HDMI to USB 3.0 video capture device + external audio technica USB microphone (soon to be an Maudio audio device and use of XLR microphones.
My setup within OBS consisted of 3 basic scences:

1. Pre-Live (containing a welcome screen, animated in .mp4 format, with an large .mp4 file 45 minutes worth of music playing in the background)
I usually start streaming the pre-live about 30 minutes before we go live.

2. Live - the actual sermon itself, broadcasting 1 x camera, 1 x microphone...and that's it. Then once the sermon is finished (usually 30 mins) it cuts to Post-live #3.

3. Post-Live (containing an animation in .mp4 format, with a verse and some background music played through a seperate .mp3 file)

Now, I know there are SOOO many other things I can do, e.g - virtual green screens, headings, etc.. (I'm actually keen on getting a 'ticker' going for the purpose of donations during the sermon but that's another question on how to do that)

I just want to know the basics on how do I transition between scenes in vmix??
I tried setting up the scenes like above, but everytime I hit transition on the animated video AND also transition on the audio file it either broadcasts the video OR the audio, not both.

If anyone can point me in the right direction how I would go from pre-live (with music and an animation) ---> to live (with the camera and seperate microphone feed, etc) that would be great.

Also I don't see USB in the drop down box when selecting the video device?? My SLR will be coming in to the computer via a USB 3.0 input (and from the SLR it will be Mini HDMI to HDMI into the capture card) so what do I select here??

Any help would be greatly appreciated. I've looked at the tutorials but nothing really addresses these 'scene' changes or setup as above (which I'm used to in OBS for example) .

Thanks!