ok iv’e tried getting the runcommand.log up in nano but just get a blank page. however i did manage to copy down the error that appears on screen which is as follows
/home/pi/RetroPie-Setup/scriptmodules/helpers.sh: line 361: “6”: syntax error operand expected (error token is “”6″”)
Panic over i sorted it . seems that a config file must have been corrupted . simply copied over my back up config files and it fixed it