Hi - I am just getting around to testing my animations in Toon Boom Harmony 15. However, when attempting to test my work, my renders show up as one large black square on the frame, or page as I have also tried saving and exporting to .mov format, too. I know I am missing something simple in the documentation. But, I have searched and cannot find any reference to my problem. By the way, I have also tried to export the files to several formats - PNG, PSD and PDF. They all result in the same. I can import drawings from both Adobe Illustrator and Photoshop, with no problem. Everything looks fine inside Harmony. But, renders and exports are all just one big black square. What am I doing wrong?
DessieX, thank you for your suggestion. That did indeed solve the problem. I am still going through the tutorials, but have done a good amount of drawing and design in the software.
Again, thank you, so much, for the info. Take care. 
Chrismom
Are you drawing with a black line? If so, add a colour card and that should fix the problem