Show help when no breakpoints are available instead of a broken form

Hello! I'm just trying out the 2beta3 version of this module and spotted something that should be pretty simple to avoid - when no breakpoints have been set up and I go to add a responsive style, the resp_img module displays a required 'breakpoints' form element with no options - screenshot attached.

Would it be possible to show a message such as "You need to create a breakpoint first before creating a responsive style" which links to the "Add breakpoint" page?

Many thanks,

Alex