Right, I got as far as getting my FBA, MAME, SNES, Megadrive, TG16, NES, and Master System romsets on there and used the scraper tool to add images! All working perfectly!
Turned it on this morning and Emulation Station freezes on loading with a white screen. Was working perfectly when I finally got to bed at 2:30am. This makes no sense to me.
Reformatted and luckily had backed up an image so at least I have my romsets there, rescraping now. If this fails again I will get a new 64gb micro SD card.
At my wits end now.