First of all, this isn't in the right board.
Second, most Japanese fangames were built with either yuuutu or nekoron engines, which were built in XP. Hourglass seems to function best on XP, so perhaps 2 and 2 go together. The rest of the engines weren't built on XP, so they don't function the same, and a lot of people use different engines for their fangames.