Hi Zuki,
did you back the original songbook up, or was it already altered?

I back all my data up every week or so, especially if I've altered a great deal of stuff.

I do a "Save All' to a usb stick.
I save it as a New Set wich I rename to whatever date it happens to be ie
All 8thfeb08. I make sure every item is ticked, because the default leaves some stuff out.

If for some reason something goes wrong down the track, any of these items, ie styles, sounds, songbook can be loaded back into my PA as a whole ( All) or as an individul item right down to a single style.
The All folder keeps opening up, there's layer upon layer of data. For instance , one you've opend up All, you'll see Styles as one of the components, if you keep pressing open, open etc you'll get right down to an indvidual style, that you can load back in.

You can also do saves of invidual stuff like the songbook. You can have 100 of them if you want to, as long as they all have different names.

Read thru the media section of the manual.

Meanwhile if you don't have a "Save' of the original songbook, I'm fairly certain I have, I can send you a copy & you should be able to load it in.

If you literally want to take the keyboard back to original factory settings, then you do it thru the resources 1.51 & 1.50 downloadable from the korg site. I don't think you can load individual stuff in from these files, that's why I always use the "All" save function.

best wishes
Rikki
if you need the songbookfile email me at rikkisbears@hotmail.com & let me know where to send it to.