if you want record your loop/beat/whatever with your mpc you must do this on the record way
press mode and then Pad 4
scroll with the data-wheel to "Rec : Record in" and tap with the cursor to "Rec in" switch it with the data whell to "Main" .
Press the do it Button & press then "play"
your loop will recorded
for the Pc-transfer you need a USB cable or a card reader for your CF-Card.
For record the beat directly in your Pc.. you should know you need a cable for connecting the Mpc (about your main-outs) with your PC (XLR8 to ...

) .