My recolors appear in all the categories except Hobbies. There the bookcases show the recolors but the exercise equipment, telescope, all games, all musical instruments and even the dart board have no recolors showing up. How can only one category of recolors not show up?

The category is set in an object mesh file (the OBJD resource), so it doesn't have anything to do with recolors showing up in Hobbies or not. It's more to do with whether the items are recolorable or not.

A lot of the original Maxis objects aren't recolorable by default, so you need the CEP or CEPextras to recolor them.

Have you properly installed the CEP?
Are the items you're recoloring actually recolorable? (Some require additional CEPextras).
Are you recoloring via the Object Workshop ("recolor" option)?