Thanks for the reply. I believe this answers the question. We could definitely just do a link but our other cloud service providers (ShareFile, WebEx, etc) supplies code snippets to customize a client web page to make the process appear to be more seamless. We also have a user meta database that contains the login credentials so we can simulate single login across all the other cloud service providers but we need to be able to pass the credentials directly to make this work.
Maybe this can be a future request. If anyone else has hacked something together I would be interested.
All the best
You can test API resources RingCentral has available today in the API Explorer: http://ringcentral.github.io/api-explorer/