What guys think?! We rarely do ..no time for that .. most of the time we just work! 😀
Jokes apart, please read: http://www.webyog.com/faq/33_20_en.html
(this may be changed soon as we might decide to do this “As a consequense localisation to ALL languages will be possible. This applies to data management as well as program's appearance.” in two steps: first Data Management, next Program's Appearance. We will detail when 5.1 final is released)
What you request is covered by “Improved management of relationships/Foreign Keys.” It is such graphical diagramming tool that we are thinking of.