Any chance you’d feel like trying rewire~ again? Not so familiar with soundflower but when i used it, there were alot more steps to pipe audio than with the simple rewire~ object. You just have to make sure to open Max first with the rewire~ object and then Reason afterwards and always make sure to close Reason first and then Max afterwards(Rewire Master and Slave order of setup and exit is important).

Otherwise, this thread has full steps on how to setup soundflower i think:
http://www.cycling74.com/forums/index.php?t=rview&th=37793&rid=1174 J-F

(5th message down on that page)

Best of luck!

Also, if you decide to go with soundflower make sure and use soundflowerbed to route the audio to your speakers so you can hear it. Often I’ve found soundflower defaulting to know output, so even though audio is being passed from one app to another, you can hear it. Soundlowerbed will enable you to route the soundflower I/O to coreaudio or whatever drivers you are using.

I’m not familiar with Reason, but in Logic I often have channels 3-4 sending audio to Max and then returning to Logic on 5-6, I then use soundflowerbed to listen in on 5-6