Hey Halldome, welcome to the forums!
Sorry for my tardy reply, I somehow missed this thread. As Val and Az said above, the game will be done whe it is done; we're not a big games company that is being paid to work to a schedule, we're all simply volunteers that are working on it as and when we can, so the more help we get, the faster we can make stuff.
Probably the most important aspect of the game will be the Artificial Intelligence (AI), which will take control of the other empires and races and basically make them play against you. The AI will also take over any order automation that you tell it to do so (Eg. colony development if you're the type of player that doesn't like micromanagement). To my knowledge, Mike (The developer), has barely started working on the AI code, although he does have some big plans for it. He's told me that we're probably looking at around a year before even a prototype version of the AI is ready for implementation. Mike also has a million-and-one other things that he wants to add or change, so it's definitely going to be a while even after the AI is implemented before the game is "complete".
You also need to know that we're trying to make the game as moddable as possible so people can change their game to whatever they want (Such as adding new ships or races, changing the images, etc). In that respect, game development will likely -and hopefully - be going on for many, many years; just look at BOTF afterall, it's 10 years old now and people are still actively playing and modding it. If people like Supremacy even half as much as BOTF, the development of the game in the modding sense is going to continue for a long time to come.
For these reasons, we can't give you a specific date as to when the game will be complete. It will simply be done when it is done.
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