You don't say if you have the MR8 or the MR8 HD. For MR8 easiest option is to use the card in the PC reader.
General option is WavManager (free from FostexInternational) see https://homerecording.com/bbs/showthread.php?t=307057
The tutorial that twitch wrote in that fostex forum in his sig was tops. Very simple, use that tut and you'll be able to import to and from the MR to Audacity and back if you like....