I have a problem on Windows regarding the toolbar customization. I haven’t tried it in on Linux or Mac OS yet. To reproduce the problem, build the JUCE demo of JUCE 1.50 or 1.52 (haven’t tried 1.51) and activate the widget demo. Then select “Customize…” and remove the first icon. After that you can’t drag any toolbar items of the toolbar, until you close the customization dialog and reopen it again.
I tried to solve the problem myself, but couldn’t as I don’t understand the inner workings of the JUCE message pump. As far as I can see, after the removal of the first toolbar item, no mouse down events get through to the toolbar items and because of that no dragging operations can start. Mouse click events on the dialog get through though.
It would be great if someone could help me out here.