i think theres a post on the best method of saving, heres mine, i have use my harddrive but im sure mem card is the same, i start with three folders, beats, samples, and programs, when i set it all up i put all sample folders into the folder names samples, by this i mean any drum sound packs or instruments that i have that are not pre programed. if u wanna sit and make a load of programs one day, make em n save em in programs, now what i do when i work on some tracks is this, at the end of the session i go to the beats folder, inside there i make a folder, and date it, or name it so il know what it is, whether iv worked on one beat or 5 in that project, then i go and i save the entire memory into that folder. shoudnt ever have a problem again, you can just go and load it up from there when you reboot, and if you want and have many projects saved, if u want to use that project next time you turn it on, save it to auto load aswell, just remember after working on that project, make a new folder similar and save it, then either delete the old folder, or if you wish to have a back log, (sometimes handy) dont delete and keep both folders, hope that helps.
peace