@t3685 ahhhh, so simple!, I was trying to use the wizards to add projects - it literally is just a .pro file with a list of sub-dirs where the next level of .pro files are! - I am sure they don't explain it in those simple terms in the docs : (
Thanks for persevering with your answer, up-voted accordingly : )
You can put the name of mkspec you are used for the given platform. I think for Raspberry it's something like linux-rasp-pi-g++. Open the mkspecs/devices folder in your Qt installation and check it out or open the Kits propertties page in Qt Creator and see which mkspec your kits are using.