In order to use Screening Room for RV's Submit Tool to upload streamable media for the Screening Room App and the Overlay Player, you will just need to make sure a few key preferences are enabled.
Screening Room Preferences panel from Shotgun “Site Preferences” Page
Whenever a QuickTime movie is uploaded to a Version via the sg_uploaded_movie field, it will be transcoded automatically into webm and mp4 formats and optimized for streaming. The transcoding preference is on by default, so you shouldn’t need to do anything here unless it has been specifically deactivated for some reason.
The other preference here that will help you with populating Shotgun with media for Screening Room and the Overlay Player is “Upload QuickTime movies when they are submitted through or generated by the Screening Room for RV Submit Tool.” This will allow you to use the Submit Tool to load up Shotgun with web-friendly media for streaming. Note that you must either be submitting a QuickTime movie, or have the pref enabled to “Generate QuickTime movies from the Screening Room for RV Submit Tool,” as the transcoder requires a QuickTime movie as input to produce the streaming media files.
Of course you also have the option to populate the sg_uploaded_movie field via the API using your own submission tools and media, or by using the "+" button to create a new Version in Shotgun or the Screening Room App. As long as the QuickTime you upload is supported by the transcoder (see the “Transcoder” section in these docs for requirements), it will be automatically queued for transcoding as soon as it is uploaded.
Once a Version has media uploaded and transcoded, its thumbnail will be rendered with a “Play” icon in Shotgun, which can be used to launch the Version in the Overlay Player. From there it can be launched in the Screening Room App or Screening Room for RV as well.