Epistolery Richard reported opening this feature by adding

[features]
editor=true

in the Med2.preferences.cfg file. This adds Battle Editor in the options screen and a map can be generated by selection. It works OK but no matter where I selected (even steppe areas) I failed to find a flat map or at least flat enough to be considered fun and fair in team battles. Every map generated featured considerable hills and a rock face or two. Nothing wrong with hills or impassable areas but in every map?
Even Ukraine steppe, elevation 190 was hills. Having to 'iron out' every map to make it fair for a map pack is a bit of a pain.

Another feature, Ctrl+F5 is supposed to show impassable and restricted areas but it would not work.
(I do not know if this feature only works when armies and deployment are created. I would expect it would work anyway to prevent you from deploying on those areas)

Booting up the PC the following day, restarting the game....no Battle Editor in the options list. Investigating the Med2.preferences.cfg file and the new lines are now missing, even though the changes were saved?

..........Orda