Had the same issue.
OtherBrotherGuy's fix worked great.
Just to clarify, for some users …
You have to open the Galaxy Forge .galaxy file in the Galaxy Forge folder (with all of the Galaxy Forge .galaxy files) with Notepad (i.e., right-click on the .galaxy file, click on "Open With," and then select the Notepad app.
The "Player" lines in the file are all the way at the bottom of the page, as OtherBrotherGuy said.
Change all of the npcOccupationalVictory text with "Normal", and all of the players will show-up in the menu when the game launches.
Thanks, man … great fix!