Can't import backgrounds. (I'm new help!)

Hi there., I’m new to this software but having trouble starting as I have been designing backgrounds and trying to import them but nothing happens.
Do you have to paint backgrounds with Toon Boom? I was using Sketchbook Pro and Gimp and converting them into various file types but cant seem to get them onto the software using export etc.
I’d like to move a rigged character around infront of these images that I can design in work in Toon Boom but would like to paint the backgrounds with other software.

Toon Boom Harmony allows you to import external content as well as being able to draw directly in the software.
This means that characters, backgrounds and videos created in other drawing, painting and multimedia programs can be brought in and animated.
You can import QuickTime videos, pictures, multilayered .psd files, as well as .ai, .swf, .pdf, and .fla files.
You can also scan images and import them as bitmap or vectorize them.

https://learn.toonboom.com

Otherwise, consult the Online User Guide.

It just doesn’t work. No error code. I just try to import an image (converted to 3 separate file supported types and still a blank canvas) and when I select it and press ok at the bottom I just have the same blank screen. Pretty frustrating as this was my starting point.
Is there a way to reset Toon Boom settings, or is there something turned on blocking the image I imported?
The tutorials just do exactly what I do but the image instantly appears and for me it doesn’t.

Fixed it with:- Windows - Restore default workspace.