sispaco

I'm having trouble installing シスパコ ～Hな甘辛4姉妹～ (dev: Atelier Kaguya Team Gassa Q), I've tried to redownload this game on different websites as well, but I keep getting the same error when attempting to press install, it seems to tell me that the GAME_SYS.EXE file can't be opened? Does this game...