HPS just released the direct download version of Tsushima.
Information about purchasing the DD version of Tsushima can be found here:
http://www.hpssims.com/shopping/shopdisplayproducts.asp?id=10&subcat=60&cat=Naval+Battles (http://www.hpssims.com/shopping/shopdisplayproducts.asp?id=10&subcat=60&cat=Naval+Battles)