Hey!
There're separate versions of the games for different platforms.
1)If you play on Windows or Linux, you need to download "Market" version.
2) Mac version is for MacOS.
3) Walkthrough is a PDF file which explains the choices in the game.
4)Gallery Unlocker is a special file you put into "game" folder to unlock all scenes.
5) There're no relationships patches. All such patches you can find are unofficial and not made by me, so be careful installing them and other mods.
Hope this helps :)