https://help.rossvideo.com/ultra/Topics/Operation/Media-Store/File-Spec.html
That section of the manual has the specifics about the media and files types. Also how to associate the audio with the animations.

Example of what the Animation files and the Audio files would look like to be associated together. Also note that .TGA or .PNG is fine for supporting Alpha Channel. I use PNG as it is just a smaller Storage size however that has no impact on the Ram Cache size when it is decoded into video space.
When it is correctly associated you will also see a "speaker" icon on the thumbnail like this:

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Les O'Reilly
Director - Switcher Product Management
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