Adding new visualisations (that integrate with other services) on the dashboard is not documented. I managed to copy an existing visualisation and make some changes to it once. It is very difficult and a lot of work and might break when you upgrade. But possible.
If you are patient, you should all vote for this RFE, which is a request to open the API and write documentation about it, so we can all build cool new stuff. There are some forum posts on the internet where this was announced, but it never materialized. So make yourself heard:
RFE: RAVE2 SDK------------------------------
Reinier Battenberg
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