If you want a really quick automated approach look into:
http://www.propellerheads.se/products/recycle/
It will put a marker before each transient automatically, then you can easily export every hit into one folder. Insta-sample
Otherwise you will have to make a copy, CMD+L then Crop Clip, for each transient event. (In session view)
Faster method in Ableton: Lay the track into arrangement view, highlight your transient, CMD+E to make each section into it's own clip. Then hit CMD+J on each sample after you rename them, this will consolidate and save them to your Ableton Library/Samples/Consolidate folder.
You could get Recycle and drop the REX files straight into a sampler like the EXS24 in Logic and then swap out the individual hits for different ones?
Or...and this is going to sound completely crazy...maybe you could try and hook up with a local drummer who has an e-kit (like the fantastic 2box Drumit 5) and get them to bang out some midi rhythms for you based on the loops you like?
There's no "right way" but what I do is chop them up in Recycle (http://www.propellerheads.se/products/recycle/) then slice the rx2 files to drum racks in Ableton. That way, you've got each hit mapped chromatically in MIDI and you're able to resequence them as you see fit. You can also use the ADSR envelopes to shape the hits, use the simpler/sampler to pitch them, etc. It really gives you tons of control.
A lot of other people just chop up the break and resequence in audio, but I never got into that method of working- I still prefer the control and flexibility of MIDI. Also you don't need recycle- you can do your chopping right in the sequencer, but with Ableton, it's a huge pain to accurately chop a break, making sure the transient markers are all in the correct place, and that you aren't missing any of them.
Most of the time, a breakbeat played at 85-100bpm is too busy when sped up to 170-175bpm, so I'll usually quantize and then thin out the break to make it flow better at speed. Then I might substitute certain hits if one or two of them don't sound great (like maybe one hi hat from later in the break sounds better than the earlier one etc). It's really a matter of taste, and the original material you're working with.
After that, I'll highpass the break, eq to get rid of ringing frequencies, saturate (sometimes) and then layer a beefy kick and snare (usually multiple snares, or maybe a clap, or maybe a rimshot, really depends). That makes the skeleton that you can use throughout the tune, layering different percussion at various times (rides, crashes, shakers, congas, tambs, etc).
> There's no "right way" but what I do is chop them up in Recycle (http://www.propellerheads.se/products/recycle/) then slice the rx2 files to drum racks in Ableton.
If you're going to use the result in Ableton why not just use it's built-in Slice-to-MIDI functionality?
Propellerhead's Recycle was the program that started it. It chops the drum hits into individual slices, and can send them to certain samplers.
Lots of samplers now have this built-in, like the MPC series, which calls it "Chop Shop." Most MPC users (including me) don't find it very accurate and prefer to chop by hand. I don't know about keyboard samplers, but I'd imagine it's a pretty standard feature these days.
bias peak pro is a good wave editor for osx.
or propellerhead recycle which is more oriented for cutting up loops for rex format
or there's audiofile wave editor
These are all pay for apps though