Thanks for the reply..
Since posting have solved my own problem and have the game working.
I was using a USB stick for my roms,
When I first started my retropie I was using incompatible rom sets, as I deleted them and replaced them with newer rom sets I feel maybe the SD card was re-copying the old wjammers rom file rather than replacing it with the newer and correct file
Frustrating...! But I hope this helps someone,
if anyone could shed some light on how to stop SD card re-copying unwanted files onto USB Would be much appreciated
Joe