When a user mouses over one of the icons, it is outlined with a faded green. After they've selected a component, however, and moved the mouse away, the description stays, but the faded green outline goes away.
Suggestion: keep the faded green outline, perhaps changing the color to a blue to indicate it's been selected.
In the same vein, if the user selects one, then mouses over another icon, the description should update to the newly moused-over icon, but return to the selected icon after the mouse leaves the icon area. You could also throw in a description-border color change.
Minor usability suggestions, take 'em or leave 'em.
I like the result, thank you for explaining a detailed user interaction. I did not implement "You could also throw in a description-border color change." because I was not sure when and how to do that.
My description border change idea was probably a little much. It's sometimes difficult to fully visualize ideas without interaction. I'd say that the mouse over behavior now is good: it's obvious what I've selected, and if I mouse over another option it's obvious that it relates what I've just moused over.