A function bound to 'set' on a viewModel is not called unless focus is lost to some other field, the window background, or a button if it is enabled. Clicking the X to close the window does not register as a change in focus. This leads to awkward behavior. Update one text field and click X and the window closes without having a chance to save the value. Update more than one field and the last field edit can be lost.
The attached Dojo snippet shows the problem. A lot of other stuff works and I will be using it a lot in my app.