Imperium Galactica II is available on Steam as well:

http://store.steampowered.com/app/490370

About the Game

Imperium Galactica. The Universe is yours... if you can handle it. The fourth millennium. Mankind has colonised the galaxy. Created an Empire. Now, it is crumbling. The aliens are restless. The oppressed are building armies. And a strange invader is headed for the heart of the Empire. Imperium Galactica is praying a new leader will arise. You.

• Detailed colony management
  
• Research and develop 100's of spaceships, satellites, weapons and buildings
  
• 7 unique alien races and 2 renegade human empires
  
• Forge alliances, trade technology, make treaties or go to war
  
• Real-time strategic ground and space warfare