For those who want to modify sea nodes in the game, a alternate way is that :
1/ To change coordinates of "central point" of sea node in the sea nodes CSV file directly. The same for coordinate of player/ennemy graph position.
2/ Then, in the editor, to change only the desired hex ( if land added on a hex, do not forget to give it a nationality).
With this alternate way, USA territory may be changed for a more "geographical look"
Question for Doom : are sea nodes concerned by some events in 1939 GC ? (if yes, I will not erase any sea node. If non, I will perhaps erase one - no sure, therefore, will see.