Of course you know that means nothing, but yes, after a few hours of hacking, I got enough of a Qt backend for IUP so a window can be displayed.
Of course those are all the widgets that are implemented currently.
If by implemented you accept "can't connect callbacks and 90% of the attributes are inaccessible", that is!
But after I get the callbacks working (that's the hairy part), the rest is simple monotonous repetitive work.
It's interesting that the Qt backend is, of course, looking quite simpler than the Motif one, and in fact, a fair bit simpler than the IUP programs look.
But hey, you get a sort of LUA bindings for Qt at the same price...
OTOH, the third step is a nicer OOP, D, wrapper around IUP.
Or something like that ;-)