The most important thing I think I can tell you regarding this unit is to be CAREFUL with the compressor.... You can easily put in 10-20 db of gain reduction before you even notice... and by then it's too late..... this happened to me before, and we had recorded several tracks already that way, and then we had to go and redo them all over again..
I would suggest keeping the compressor around 2:1 or below, and if you absolutely HAVE to (big rock guitar outro or something), 3:1. I tried 10:1 once and it was just one straight line. Keep the compressor knob below 6, and put the attack as high as it can go (11 ms). 250 ms is slow enough for release, so you can keep it around there. That should hopefully give you some nice compression, but nothing too drastic. Eq-wise, I keep the Low flat, add about 1 or 2 db on the highs, and about 2 db at around 3k on the mid (be careful though, if you have a sibilant singer this will get REAL harsh).
For acoustic guitar, I would turn the compressor knob to like 3, the ratio at 1.2:1, and the attack as slow as possible and around 500 ms on the release. Of course, you may not want to add any of the compressor at all.
Hope this helped you out some. Remember, I'm still learning it as well, so don't take EVERYTHING I say as concrete truth.