I think you need to have the .cfg files for each nozzle size which point to the specific printer platform definition or you're going to get an empty list when you try the nozzle selection pull down menu. The .cfg files do this on line 4 I think:
definition = creality_ender3Max
The materials are all there since they're in the base_creality definition but the materials show up as not valid since there's no nozzle defined.