Wouldn't it be interesting..

.. if MaxIDE was actually stable on Linux, and didn't want to crash/hang/annoy at every given opportunity?

That would probably require creating a MaxGUI wrapper for QtMax (itself being a BlitzMax wrapper for Qt).
There are many advantages to doing this. The main one I see is that I get to test QtMax and check that I'm implementing all the things for all the widgets that I need to be. So, for example, any widget subclasses really need to implement all of the inherited event handlers and so forth. For example, a QLabel should implement inherited events from QObject, QWidget and QFrame, as well as its own.
It's not a difficult job, there's just a lot of it!

Having a rummage through the GtkMaxGUI source, it is incredibly messy down there. I think the main reason is that raw Gtk is harder to use generically.
As an example to show how easy it is to create a CheckBox for use in MaxGUI, here's some basic code :

Type MaxGuiQCheckBoxButton Extends QCheckBox

Field gadget:TQtGadget

Method MCreate:MaxGuiQCheckBoxButton(text:String, parent:QWidget, owner:TQtGadget)

gadget = owner

Super.Create(text, parent)

Return Self

End Method

Method OnInit()

connect(Self, "toggled", Self, "onToggled")

End Method

Method onToggled()

PostGuiEvent EVENT_GADGETACTION, gadget, ButtonState(gadget)

End Method

End Type

We extend off the QCheckBox, and simply connect to the "toggled" signal, posting the subsequent event back into the MaxGUI event queue.

Notice too that we are only using pure BlitzMax code here. All the nitty-gritty interaction with low-level Qt is handled by QtMax. No externs, or glue code to be found!