I have similar issues importing on mac using 2017.15 and macOS 10.12.6. I have a macbook air (13", early2015) according to "about this mac". I have to select my model first (allow cell to go blue), then double click on the available model (so it goes blue and mine goes grey), then double click back in my model, If I want to import the same model to others models I have I can double click down. I cant get drag and drop to work. I watched the release video that Keith did showing how to do the import, but wasn't able to concentrate on it fully as i was distracted. Just didn't get a chance to go back and watch it again, but it did look like I should be able to pick up the import model and drop it on mine?