try gettin a few (not to many) clips goin in live. Play about with the loop start points, pitches , envelopes, etc.
Dont add to many fx yet, and see if you can get them working. (dont give up to fast, you'll be surprised).
when you're happy with whay you've got, hit record on the main tranport bar and trigger your clips at say, a 1 bar quantise and record 65 or 130 bars. Once you've got the rough arrangement down, go in and work on the detail.

I know its a cliche, but its all about plugging away at it.

hope i did'nt ramble ;)