ok, i found something for anyone who cant get it to work!
to use it with midi / ableton, you MUST put the [midi.xml] file in your HOME folder. NOT in the midi folder that they give you.
so, it's actually quite easy, just get the program from the reactable site, then unzip it and stick it in your HOME folder. ([your drive]/users/[your name]/reactvision folder.
like that.
then,
pull the demo.xml OUT of the folder and into the home folder.
THEN run terminal:
./reacTIVision-1.3/reacTIVision.app/Contents/MacOS/reacTIVision -m demo.xml
VERY IMPORTANT!!! have the IAC driver enabled in the audio/midi utility and ableton.
then run
./reacTIVision-1.3/reacTIVision.app/Contents/MacOS/reacTIVision -m demo.xml
then open live!
it should work.
hope this helps people. it took me DAYS of troubleshooting.
it's way cool once it gets going. well worth it.