I have the 12-50mm, 60mm macro and 9-18mm wide and only one port: The 4" semidome which fits all of them.
With a couple of 3D printed zoomgears (I bought the "austrian gear") and the diopter flipholder, you are all set to go (optionally add a +2 dry diopter to the 9-18mm for added corner sharpness). It works like a charm and I don't miss the macro-mode on the 12-50mm at all. Having only one port for these 3 lenses saves money and more importantly: Travel weight.
There is a discussion about this setup elsewhere in these forum which convinced me to go for this.
PS. Why would you want to use the 14-42mm if you have the 12-50mm?
EDIT: Ah sorry - I realised too late, that you already bought a setup.