As you know, we're working on RV/Shotgun integration which goes well beyond "click to play" functionality, but I wanted to point out that you can get at least that far with RV 3.8.4 without any additional code.
Then you can make "url" type fields in shotgun to play your media, like this:
- Add a "Play In RV" field to your Versions of type "url" (you'd want more than one field if you have more than one media type, saymovies and high-res frames).
- For each Version, edit the "Play In RV" field to "Link to Web Page" (not "Upload File"), and set the "display name" to "rvlink", and the "Web page address" to the approprate rvlink URL. (The format of rvlink URL is described in the Knowledge Base entry referenced above).
- Then that Version will have a field with a hot link labeled "rvlink" that will start rv and play the Version's media.
Questions and comments welcome ...