song mode saves automatically just like the patterns. IN song mode, you put the patterns in order that you want them to play and thats it....Its actually pretty simple......If you make changes to the pattern, the changes will be applied to that pattern in the song also.....Im not sure on mastering though....I think you can use the mastering function to apply to the whole song in song mode......

Best of Luck
Tweek

Thank you for helping Tweek. I had a look yesterday and discovered this also.

soo i dont have to do any saving? But what about all my drums sounds? I have to load those back up 2?

Nope. Your drum sounds will remain where you put them, UNLESS you actually delete them. Pretty cool system - although it can make you a bit lazy