I really love the way Stardock is supporting those who bought into this game early. It's truly fantastic.
But...
I now have Galactic Civilizations I and Galactic Civilizations II and all expansions for both, bought from Stardock that now require me have Gamstop's PC app.
I have Sins of the Solar Empre and all expansions, bought from Stardock that now requires Gamestop's app for the earlier stuff and Steam for the most recent expansion.
And now I have Elemental, also bought from Stardock, the latest expansion of which also requires Steam.
I bought these games from Stardock because I wanted to support Stardock and in particular Brad's enlightened attitude toward DRM and how it punishes legitimate customers. If I wanted to support Gamestop or Steam, I would have bought from Gamestop or Steam.
However legitimate the business decisions and restructuring have been at Stardock over the last few years, I do feel like I've been the victim of a bait'n'switch to a certain extent. I don't want these 3rd-party apps on my systems and, with all due respect to some of the other posters, the fact they have no problem with it doesn't negate the fact that I do.
I really, really encourage you to pursue releasing your catalogue on gog.com. I will buy every single one of these games again via gog.
I once owned many Stardock games. I would like to again.