Well getting an RTS to work on Unreal is not going to be very difficult. It will obviously take time, but we definitely need 3D art. While I'm practicing 2D and 3D art I'm currently nowhere near good enough to do anything more than drawing up concepts. So creative works aren't out of the picture.
With Unreal I'm new, but I've tried stuff out, and it's not going too be difficult to learn. (for parts that are relevant to your field) We should be able to get up to speed with it pretty fast.
The SourceForge project does not really have anything of value for continuing a project, not too much effort was put into it. It was just a small attempt when we wanted to make changes afterward with switching engines and whatnot. Of course we had not moved on sooner because we had been busy.
Of course we will set up version control later; probably with git.