QML rect property as a parameter causing a crash

I built QQEM with dev and noticed it was not starting. With some testing, noticed a strange cause for this: Calling a C++ method with QML rect property as a parameter. Commenting out line 17 of qtquickeffectmaker/tools/qqem/qml/ProjectSettingsDialog.qml makes it work:

//effectManager.setEffectPadding(newItemPadding);

Also changing it to this works:

effectManager.setEffectPadding(Qt.rect(0,1,2,3));

That newItemPadding is "property rect newItemPadding".