Hi vip, This is what I did prior to loading OS2 on my pa2x and I reloaded all the saved parts that I needed to after the Install. Everything is as it should be. All my 'custom' song styles, voices, pads etc. are OK. No problems at all.
Go to Media page
Go to ''SAVE''
Highlight ''ALL'' Folder
Press ''SAVE TO''
Then choose H'D
Then ''New Set''
Name your Set using the 'Text' String
to the ''Save all page''
tick all relevant Box's
Then ''OK''
Are you sure ''YES''
All your styles, sounds, pads, songbook will be saved for retrieval later.
This is at your own Risk as I'm a 'Newbie to Korg' for a few weeks only so I'm just finding my way around everything, however, it worked OK for me..........
I hope someone more knowlegable on the Forum confirms this for us as I wouldn't want you to have problems. However, it won't do any harm to save everything as a Backup in this manner

EDIT:
says this on the Korg Site
Note: After installing this new Operating System, please also load the new Musical Resources (2.0). This is mandatory with this OS version. If the User area contains custom data, please save them to a storage device (by using a Save > All operation) before loading the new resources.