Well, I did quite a lot of work over past two months, and finished hundreds of points on my to-do list. By now, the C++ source code encompasses about 260,000 lines (over 8 megabytes). (Printed out, that would be about 4,350 pages, or, on line printer paper, a paper trail of 1,030 meters or 0.64 miles.)
The game looks really good by now. It will include all of the features discussed in this forum (including construction of houses and trade).
But it will still take several months to finish everything (and since Beta-testing doesn't make sense while the program is still incomplete, that means it'll still be some time before I'll release a beta version, too).