@pyr0cide Just leave the exports on the server

/volume1/roms 192.168.1.*(rw,async,no_wdelay,no_root_squash)

And make sure you use the proper case when referring to the share name, i.e. not mixing upper-case with lower-case

mount -t nfs -o vers=3 192.168.1.6:/volume1/roms /home/pi/RetroPie/roms