Is this the full game or just the .exe file? From what I know, the full game is 4GB as you have, while the .exe file should only be 4000KB. If it is just the .exe, is there any reason for the larger file size? If it's the full game, please tell me that it is the MangaGamer/Steam-independent version that has no reference to Steam, as opposed to this version: Dies irae - Eroge Download | Eroge Download where it's just the Steam version with a Steam emulator .ini file.
Edit: I just checked the file. Apparently, it is the same one listed on this site's downloads page. In other words, the Steam ve