Adding 4PLCC LEDs

Not quite correct, I bussed the two cathodes (which cause an internal conection) and what I thought were the two anodes so you need to change that to bus the three cathodes together. If you click on the middle cathode pin in schematic view you will find both it and the now single anode pin light up yellow (indicating an internal connection) which is incorrect. Instructions for doing this in parts editor are here:

(I tend to edit the fzp file directly which will also work as long as you know the file format).

Unfortunatly no, they need to be separate parts. With some file editing magic to convince the part it is part of core it is possible to make the different colors selectable from inspector though.

Peter