This is what I found in a "Tips & Tricks web site" about the question:
"Question:Can I specify the color of the part as item in a family table?
Answer: Yes, you can: you first must set a parameter named color,if you'd like, with a value "black" for instance. Then "add item" to the family table (Fam table/add item) and select "parameter/color" from the menu. Of course, your initial value (black)will be attributed to your generic model. You can add an instance that on the "Color" column would have any another value(natural,etc). You can see your model parameters in the tree by adding the column for the model parameters."
I hope this will be a solutions.
Bye!
emproe@katamail.com