I could be wrong George, no programming guru to be sure, but I think the boards pull in on an as needed basis. So if I synch on you and you have boards that are more up to date than mine, it will go out and get the needed boards for me. I believe that is how it works. On an, as needed, basis.
Carl, I believe you are correct. What it won't do, however, is get a board that does not exist already on a local drive. To get boards for the first time, go to VASL.info.
Board 75 is done and should be appearing on VASL.info shortly. Just having a final glitch with posting it to the site.
And just for clarity's sake you don't need to sync with another player to trigger a board update. If you open a game with a board the update routine checks for a new version. . . . so long as your computer is connected to the internet it should work.
The drop down list is a list of everything you have in your boards directory. If you have not downloaded stuff, it will not appear in the list. Once you select a map, vasl calls home and checks to see if there is a later version. If there is vasl downloads the later version. Occasionally the master list is out of sync with the actual board versions. Hilarity ensues.