You can find the date and version number at the bottom of "PROGRAM\globals.c".I had no idea where to change that. Or rather I have never noticed the date there. So @Jason, the install can be perfectly ok anyway.
If you change the version number, the game will not recognise savegames from a different version, so only change that if there are things in the update which will break old savegames. (I changed that whenever some system variables changed. If you loaded a previous savegame, you could continue, then the game would crash when you tried to save again.)