This unit is the RT4 and RT5 system and is made by Magneti Marelli
Main differences between RT4 & RT5 - RT5 has Bluetooth Hands Free, faster Navigation calculation and on C4 & C4 Picasso only, USB ports and a High-Res screen.
Try making a folder called "maps" on the SD card and put everything inside of this folder and try it again. I think I had to have two maps folders before it worked on my RNEG.
So you have MyWay then not RT6! That will explain it. I thought you were referring to the eMyWay. Do as Elis says, the content has to be right for it to be recognised.