Hi @fonderco - our Public Logo Model is actually undergoing maintenance at the moment but in general it is not possible to add concepts on top of our existing models.
A custom model will look at the entire image as you have suggested so we do recommend training the system on cropped images of it from a variety of zooms, angles and lighting sources. You can also train on some images that aren't cropped but you'll want a decent amount that are (without adding any duplicates, as that wouldn't help).
Let me know if you have any other questions on this.
