That part's appearance is indeed black, it's just reflecting the light gray bottom half of the active HDR. So in essence it's a lot more photorealistic than what you see in SW, since that is the ultimate goal of 3D visualization and, of course, Visualize.
You'll find Visualize is much smarter and easier than you think
So you have 2 choices, which both a very easy:
1) Enable the orange Appearance selection mode to select that specific Appearance. Go over to the Appearances Tab in the Palette and make sure the color of the appearance is 100% black. Then you can adjust a couple other settings, based of the Appearance Type, to make it more black (less reflective). Select the Appearance Type that most resembles what this part would be made of in the real world. 'Plastic' should give you the look you're after, and you can adjust the 'Highlight Color' to slightly darker as well:
If it's a Paint, then reduce the 'Clearcoat.'
If you really want it to be black as night without any reflection or value shift, then choose the Appearance Type 'Matte.'
2) Keep the Appearances as they are, but select another HDR.
Have you watched the 16 Visualize tutorials on MySolidWorks to help you along the way? Here is the link:
Visualize is awesome , give it a try
Finally I am getting the hang of it so I changed the topic.
Keep at it!
To your other point, we are planning to provide loads of very short 'Quick Tips' videos in the next couple months, likely available on our main website. This will help fill the gap between the broader tutorials.