for the heck of it, I right clicked a cover art image in MOG, and discovered I could save it to my computer.

 

to get the artwork, here are my steps.

 

I find the album I am wanting the cover art for and start it playing. Then I click the rectangular button in the top right of the MOG window.

 

 

Then I get this screen

 

 

right click the image and save as

 

 

and you get the cover art, name it whatever you want and add it to your files.