you accidentally added the "tests/updatechecker_t.h" in the release section instead of the debug section, thus the release version won't compile anymore. It gives a "QEQUAL was not declared in this scope" error. However just moving it into the debug section didn't help and I couldn't find the error.
PS: Thanks so much for fixing the PDF page jump bug, that was one of the most annoying!
Did you get your Qt4.8 to work? Otherwise I just had to zip my dll's anyways, so if you are still interested just tell me.