I didn’t try the link you provided but things seems to be working now.
Vassal changed its address not long ago (I got that event on BGG), and when I tried to old address I was getting messages like the one from Skippen. However, I went with the new address, as provided from BGG, and have had no further problems. The address change was small, I can’t remember it for sure now, but it involved (basically) the difference of one work in the address.