This game, made by "DarthMod" (those of you that played RTW back in the days will for sure remember his great mods) is a really good and fun game, IMHO
Visually beautiful (stunning, IMHO), great and fun RTS (pausable) gameplay, and a very good depiction of Gettysburg battle. It has not the depth of Scourge of War games, but can be played and enjoyed in short gaming sessions.
I would say a must buy for American Civil War fans and a worthy sucessor of Sid Meyer's Gettysburg, of course.
And it costs only 11,99€ in Steam - and plays in Mac, too