I will at least make sure the current Qt 4 based GUI still works on the N9 with new modRana version, but other than that it doesn't look very likely I will be able to to work on it much. Also regarding routing, vector drawing is basically completely different with Qt 4 (QPainter only) and Qt 5 (the hardware accelerated & tiled Canvas can be used), so at least for drawing the route there would basically need to be a separate QPainter drawing path only for Qt 4.