Goodmans GNAV22 won't read maps from SD card

[xGAME-OVERx]

Hello! My father recently purchased an (old style) Goodmans GNAV22 dirt cheap, but the UK/Ireland maps on it are corrupted.

I have tried to delete them and reinstall the maps from the supplied discs. This did not work for 2 reasons:

1) Device claims to have insufficient memory
2) The CD is scratched and one of the files can be read

If anyone has map data for this unit, could I please get the file I am missing? I'll check what it is tomorrow.

I'm not sure if anyone has experienced problem 1 before, but I really dont get it...

Anyway, I proceeded to try and install the UK/Ireland maps to an SD card - which was successful. However, the unit does not recognise the maps on the card.

Has anyone had this problem before?

Does anyone know of any fixes for any of my problems?

Thanks in advance
Scott