Taking out the batteries and SMC eventually did the trick (had to leave it like that overnight).
Everything now working fine.
Many thanks for the help.
I apogise in advance for my stupidity: I have only just got a FLU GP and have downloaded all the initial bits and pieces, registered etc. and have put Freelauncher on the SMC. I went into Freelauncher before copying any files to use with it (probably a mistake I now realise) and get the Korean...