Currently experiencing this issue myself. I created a 2-star system with 4 players for a 2v2 and am trying to set the team spawns so that team 1 spawns in one system and team 2 spawns in the other, but when I use GF it sets max players to 0.
I've spent the last 3 hours googling and found the "Manual fix" by opening notepad and setting playertype to "Normal" but when I did that, and tried to even load sins of a Solar Empire to select the map it instantly crashed and would not function until i went to the save folder and deleted all my maps. Now i can select maps and even play the one i made using the In Game map designer, but I can't set fixed team spawns and no matter how many times i try to restart the game it seams to guarantee my team mate to spawn in the opposite star system.
What do I do?