If I can get hold of a Win7 computer to install it on I'll see if I can find where it puts its saves.
Going by what the saves from the save game server look like, your saves probably have names like 1a.txt, 1b.txt, 2a.txt, 2b.txt, etc. which correspond to the save slots. If you installed the game into your Documents folder, they will be found in a subfolder of the RHEM4 folder.
If you installed in C:\Program Files(x86) the game may put saves elsewhere if it's having trouble making changes inside C:\Program Files(x86).