The library msvcrt is something produced and distributed entirely in Microsoft house, not a piece of Freeciv. Guessing, it seems to me like a missing handler to manage video memory. However, you'll for sure need to get a more recent version of that library which contains the missing handler. Whether this is possible by just upgrading Windows 2000 via the built-in software updater, I don't know. Installing Windows XP would likely resolve the problem, since it would provide a more recent version of msvcrt. If you feel to experiment, you could backup that msvcrt.dll file and replace it with Windows XP's one. In case it won't yet work, restore the backup and say goodbye to the years 2000.