Formalities for video submitted with paper?

A conference mentions "Supplementary material (images, video, etc.) may optionally be submitted with papers, must be submitted as a single zip file and be no larger than 100MB.".

So along with my conference paper, I’m considering submitting a video that shows the working of my program. Few questions:

1. I couldn’t find any specific info on how to mention or cite in my paper that there is a video included with the paper as a supplementary file. Can I just mention "…in minute 2:05 of the video included as a supplementary file…"?

2. Since the video has no audio, I’m considering adding to the video, some pleasant background music that’s from a website which allows such music to be used royalty-free, but asks us to cite/attribute the creator of the music. So firstly, is it proper etiquette to use such music in a conference paper submission, and secondly, how would the attribution be mentioned? In a separate text file or as a citation in the paper itself? Also, is citing it enough, or do I have to explicitly obtain the creator’s permission, in the same way, publishers ask for proof of copyright consent from the creators of images when I include somebody else’s image in my paper (even after I’ve cited the source)?