None of the rv/shotgun integration, including "play in rv" will currently work if the hosted Shotgun site is behind a proxy. Even "play in rv" just provides rv with a Version id and then RV must contact the server to get all the info for that version (including path to frames, etc), and that will not work if there is a proxy in the way.
It would be great if RV could communicate with Shotgun, even if its behind a proxy server.
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