For some odd reason, my BIAB 2017 Audiophile edition has some of the tracks in the mixer windows grayed out. They still work, but they are grayed out. How do I get the tracks back to either showing the yellow color or the green color?

Usually a grey track indicates that the track is empty or "disabled". There is a menu for each track where you can select to either "disable" or "enable" the track. After looking closer at your image, it appears to have been put on "Disabled", so that's what you have to change and then you should be fine.