As mentioned in subject, there should be more supported "out-of-the-box" touch-screens in Boot2Qt image. At the moment supported displays are listed here https://wiki.qt.io/KnowledgeBase:SupportFAQ#Qt_for_device_creation
ADDED: There was a request about this particular display https://www.raspberrypi.org/blog/the-eagerly-awaited-raspberry-pi-display/
ADDED2: the was a request for this display support LM700-MU. Specification is attached.