Saving a ROUTING does just that, so it will not save MIDI info. If you want, you can save a SETUP instead, which contains the routing and the other setup info.
If you save a user group to a card, it will remain on the card if you take the card to another machine. This means that you WILL see the MIDImap on the new machine. You may have to select the it on the SETUP/MIDI page, unless you have also loaded the SETUP from the card.
Note that a saved SETUP is not guaranteed compatible with future software updates (hard to predict the future).