Hi!
First, I recommend you to install from repo the 5.7.1 libs of QT. 5.7.0 seems so unstable
About your problem. Can you post the .pro file here?
I'm not developer of this library but so active user and tester of it, as you can see.
Alex is ill now, may be I can help. In other case will be wait of them
And tell me, what version of LM you are using? from git?