The raw file format is manufactorer and model specific. I guess the F in RAF stands for Fuji.
Any raw converter has to be adapted to newer camera models. So older software versions might not be able to read newer files.
Conerning JPG and RAF you should check your settings in the setup menu.
I‘m aware of this. I‘m used to X-Cameras like the X-T2. When I‘m using a Fuji wide angle lens the camera compensates most of the edge distortion (if the lens is known to the camera, new lens profiles are included in firmware updates).
Shouldn‘t there be an in camera correction for the lens to compensate this effect? Maybe it must be turned on or the camera doesn‘t recognize this lens.