BASIC is every bit as modern as any other language and structurally equivalent to any modern static language. It's more verbose than C and similar languages [...]
Verbosity is the problem.
If I were fine with the screens and screens of the boilerplate code, I would have simply used the Java.
I don't understand why you couldn't get QtCreator working. Qt is easy to install and use on Ubuntu. And the Qt QUI designer is very easy to work with.
As I heard it was a systemic problem back then: not all package dependencies were declared, meaning that after installation you have to also install bunch of other stuff to make it working. (Many years ago, first time I tried QtCreator, it actually refused to run, because some linked libraries were missing.)
I'm not sure about now, but back then it wasn't even close to anything RAD. It was only a helper to create the GUI in a XML form, which was back then not even properly integrated with the rest: one had to write some code manually to actually tell Qt what resource corresponds to the window. And add resource manually to the resource file.
I would say that Python + libglade + glade is also a pretty good combination. It's not quite the RAD experience you seem to want, but it is a fast and powerful way of developing GUI apps, thanks go a nice API and Python.
Yes, it is not RAD. And for that I already use QT + C++, which provides very powerful, simple and no-fuss API to build GUIs dynamically (without external UI building tools like glade or Qt Designer).
The problem is not me per se - I have no problems with most of the stuff. The problem are the other team-members who are not well versed as me in the scripting languages and building GUIs. On many past projects I have left behind lots of stuff which 95% of coworkers can't support or develop further. And I want to solve the problem by throwing in something that requires as least boilerplate as possible, stays as close to demos/examples as possible. I'm simply trying to find something to help the people start moving in the right direction.