EzFlash V and save files

Ok so I have my EzFlash V and running the latest kernel (1.6 I think) and I'm loading Roms and they're working great.
My question is about the save files. I regularly make a copy on my pc of the SAVE folder incase I lose the data but just recently I tried to replace a .sav file with another from my other EzFlash which is a bit further in the game but it didn't work.It always reverts back to the original .sav. I think when you start a game the EzFlash copies it's own .sav onto the microSD and overwrites it.

Is there any way to reload a different .sav file from the microSD? otherwise it's a bit pointless me backing them up.

Sorry I think I put this in the wrong section.