Thanks a lot for the quick answer, I'll try to do it then. I have a quick question about fighters: considering in this game you can just do everything, I was thinking: is it possible to train grade of fighters making fight them each other, a way to test them in battles and train pilots (taking the risk to lose them of course). I was just wondering if this is somehow possible.
Using SM, you could make another player race, just with no population: call it 'RedFor' or whatever you like. Then transfer the fighters (or any other ships you want to "wargame") over to RedFor's control. I believe there is an option to include a ship's officers with it when it is transferred, if not you'll need to transfer the officers you want to use too.
Set them and your empire to hostile to each other and voila! Now you're ready to do an orbital version of 'Fleet Problems'. You'll have control over both sides and you can fight it out. You may need to get creative when it comes to resupplying RedFor if it's a multi-day exercise. You could transfer full tankers, colliers, and supply ships to their command to do this.
To keep the leathality down, you could consider making training missiles that only do a single point of damage and ruling that any ship hit by one is "dead" and get's transferred to a neutral side. I think 0 damage missiles might work as well but I can see that being the kind of thing that'll throw an error (anyone know?). Bare in mind that damage to the internals usually causes casualties so whether your race does live fire training exercises probably depends on the society your roleplaying.
Edit: I personally wouldn't do this unless I had a in-universe canon reason to do it, since it's a lot of effort for not a lot of payoff. For example, I believe one of Steve's multifaction AARs had the Europeans and Americans do a joint exercise to simulate an invasion of Jupiter and its moons in response to perceived Russian or Chinese aggression.
Edit 2: I was playing around and couldn't see a SM function to transfer ship so this won't work in the current version of C# (1.51) unless I'm being blind.