Pyside/pyqt motion builder dialog locks viewport


I have been looking at using PYQT/Pyside in Motion builder to try and build some better tools/ tool UI but whenever i run any QDialog code it locks the perspective viewport and i cant pan or rotate but CAN zoom with the mouse wheel. its super weird. To “fix” this i have to double right click which brings up a popup menu (Insert/Delete/Rename) which then unlocks the viewport and i can pan and rotate again.

I have tried my code and others on teh autodesk webiste and it happens with both so i think i must be missing something with QT. Also i have tried this in MoBu 2014 and 2015 with the same result and am now installing the latest version to see if it is still happening there.

Has anyone else had this issue? I have read everything i could find on Pyside/PyQt and nothing is mentioning this issue or a solution

Thanks for any help