a small glui problem

Hello to everyone!
I’ve recently wrote a small application with the help of glui. The app consists of a main window and a subwindow which contains the glui objects. In there I do some file loading stuff that usually will happen everytime the application starts (but cannot be done automatically, the user provides the filename). In the main window, you can say I have a canvas that I place colored balls on it and use some keyboard shortcuts for convinience. My problem lies that when I load a file, the subwindow gets keyboard focus (normally). But when I return the mouse to the main window I’d like it to receive keyboard focus immidiately (like putting it in the mouse’s passive motion callback) so I can use the shortcuts. Otherwise, I have to click to my window, which adds another ball. This is rather irritating. Does anyone know a function from glui where I can pass the keyboard focus back to the main window only with the passive motion of the mouse? Thank you for your time.