I have created a custom column called "Type" that contains--you guessed it--the type of ebook document. I notice that, in the left-hand columns browser (not sure it's called that), when I open the "Type" column, some of the icons are faded and others are not. What does this mean? I also notice that sometimes I get a green plus mark instead of the column icon; what's that all about. If I click the green plus mark, it become a red minus mark. Can somebody tell me what this is all about?
I have added a screenshot below to show what I'm talking about.
Thanks
gsw
