Will M. Baker
Re: Request: Thunderstone on Vassal
The Yucata version is excellent, but they only have the license for the base Thunderstone game plus about half of the first expansion (Wrath of the Elements).
There is also the Facebook version, which has (I believe) all of the base game and a bunch more available for purchase (via Facebook credits).
Facebook has all of the base game, Wrath of the Elements, Doomgate Legion, and most of Dragonspire (there is still one Dragonspire pack "coming soon").