I have all the built-in system and software artwork classes implemented, as well as 11 additional classes of images, and system videos. It's not that hard.
Tools\Options\Front end\files & directories (note the author has called system snaps 'Previews')
Make sure to read this: http://wiki.batcom-it.net/index.php?title=The_%27ultimate%27_guide_to_QMC2
Then, if you are still stuck, ask again...