Change font color to dim a fcTreeView item or disable an item

In a VCL fcTreeView that I am using as a menu, I would like to leave all the tree as it is but be able to selectively disable some entries if that will cause them to visually indicate this disabled state, or just be able to dim the black text by changing the item's color to gray for selected entries.

I see that UseStyleFontColor can be set for an Item but I cannot figure out what it does and I see no way to use a Style, anyway.

Or is there any other Woll2Woll VCL component one could use lieu of fcTreeView for a menu tree such that the color of its items could be managed in code?

Can you advise?