[LAD] Qt GUI for LV2 Plugin

Hi all, I am thinking about making a custom GUI for the Autotalent LV2 Port, which would allow the user to select scales easier and perhaps provide some eye candy ;). It seems that there is some issue with LV2 GUIs being not cross-platform because they require GTK. Therefore it seems to make sense to create a GUI using Qt, so it will work on most imaginable platforms. However, when I started googling, I found a discussion on the topic by the author of the Composite sampler, who wanted to do the same thing. It seemed like he was actually writing a new extension in order for this to work. However, I couldn't find any further work on that project, and currently the Composite plugin doesn't have a custom GUI at all. So my questions are: Is it possible to create a Qt GUI with the currently designed extensions? Which extension should I use if so? Which hosts support which type of external GUI creation? Would it take additional code to get any Qt GUI running under them? Is there any reason I should not use an external Qt GUI? Where should I start with getting an external Qt GUI to run? Thanks, Jeremy