ok, if you are running the original sins you follow this path to save maps:
c drive>program files (or program filesx#)>stardock games> sins of a solar empire> galaxy
This will put the map along with the other maps of it,s same player size
if running entrentchment you got a whole new problem.
First set up your computer to show hidden files, then use this path
(user name fille) >Appdata (this folder will not show up if you do not have files unhidden)>local>ironclad games> sins of a solar empire> Galaxy forge
this will putthe map in the galaxy forge tab.
please add rep if i helped any
have a great time playing soase!