Ok, topic is a few weks old but if you're still stuck on this...
You should read this :
http://embedded.von-kannen.net/2014/05/21/qt-4-8-6-on-beaglebone-black/
I use tslib for touchscreen under Qt4, and you can calibrate the screen with
ts_calibrate and then use the touchscreen for qt apps.
I
I've customized my distribution; the intentions are to run Qt either to the
XServer with no display manager, or directly off the frame buffer.
I did start with the default Angstrom 3.8.13 kernel and root file system.
I don't believe I customized the kernel at all with the exception of
