File sync is only available for My RealDash subscribers. See this post for more details about purchase options:
RealDash purchase options - General / Frequently Asked Questions - RealDash Forum
By default, RealDash does not stretch the dashboards to different screen aspect ratios. This is a design choise to make sure that round gauges always remain round, and relative distances to other gauges remain the same regardless of the screen size.
Because of that, we had to make a compromise with our dashboards to design them into 16:9 aspect ratio. With no stretching, 16:9 aspect dash will leave borders to left and right. We offer some dashboards with wide versions that are match for 1920x720 wide screen.
This has been discussed previously, for example in this topic: