Right now with RIAB (if I'm not mistaken) designers must design UI around the lowest resolution available in order to avoid players with low resolution being unable to play due to UI overlap/passing out of the screen area. Designing around low res, however, will leave high res players with a very sparse and potentially illegible UI due to small font sizes, etc...
With no options for the designer to create different UI setups for different resolutions (ie script conditionals based on current resolution), there is no solution for designers here besides a tiny UI for high res users or disclaimers that the game should be played windowed at low res.
One of the main features that drew me to RIAB was the visual tools with which great UIs could be designed very easily and intuitively. My game project is a language learning game, so it is UI heavy and text heavy. I find myself at the point now where I used all of RIAB's great features to design the mechanics for my game, but because of resolution issues, it may only be a proof of concept which will require another engine to bring to fruition. I've used a great many game engines, and RIAB is by far the most fun and friendly and easy to use. And its suite of tools make production so fast!
Anyway, I think there are multiple solutions to the problem posed at the top, such as forced resolutions in a fullscreen/borderless windowed mode, or giving the designer the ability to read and react to current resolution (ie design UIs for various resolutions). It would seem, however, that a scaling UI is the easiest solution for designers and the most user friendly option for the players.
fin.