Quick update - By leaving all tracks armed you can simplify the MT setup hugely. simplified rig is running perfectly now, including automatic bouncedown when you come to channel 8 allowing you to keep overlaying!
This means a rewrite of the tutorial, but it's much easier to setup and understand now. ETA less than 48 hours, so watch this space.
I'd really like as much feedback from these forums as possible before I go plastering it over ableton's and any other places I think it will help people out.
For those too impatient for the full guide, and who just want their hands on the files, you can download them here:
http://www.mohawkmedia.co.nz/MGO1files.zip
the MT setup responds to MIDI notes E0-B0 in semitone steps as this is what's output from my US-428. The ableton file is version 6.05. Here's a screengrab of the ableton setup, with and without keyboard assignments overlayed.
Pay particular attention to the Inputs/Outputs and monitor status for each channel. Channel 9 is an 'input strip' to apply and insert effects.
You MUST turn off the Computer Midi Keyboard in Ableton (CTRL+SHFT+K), turn off exclusive arming in the record warp launch panel of the preferences dialogue, and finally set your quantise to 1 bar.
You also MUST select the 'safe' preset in MTpro before you start. The whole thing works by changing MT presets to add additional keystrokes to stop the current recording.
Feed your MIDI device into MTPro, and all ableton control is then done via keystrokes. If you can't get your MIDI controller to spit out the right notes (E0-B0) then you'll have to go and edit the MTPro file. tiresome.
Use: start ableton playing. hit any track 1-7 to start recording into that slot on the next bar, and either hit the same button to stop, or hit another button to switch to recoding a new track. channel 8 will resample the entire thing, and when you stop recording it waits 3.5 seconds (over a bar at 90bpm) then cuts/pastes the previously recorded clips into a fresh slot, stops them playing and clears the decks for fresh recording, all the while keeping the resampled loop chugging away. Couldn't be simpler!
I hope this helps you guys! I have 20 days left on my MTPro trial - maybe if florian likes the tutorial I'll find myself with a freebie hint hint