So I've been using reason on vista for about 3-4 months and I just got a mac specifically for music. It is a g5 with two 2.3 processors, 4 gigs RAM and a bus rate of a little over 1 ghz. I open one of my tracks and hit play...dsp spikes and it stops.

Can my system magically not handle this while my core 2 duo 2.0 w/ 3 gigs RAM laptop can? Anyone know a solution?

hmmmm , Reason projects should be compatible in MAC and WIN ... , so that option can be left out ... ,
Just a quick mindrush ... , do you run the same Reason versions ? (4.01 on the win , and 4.01 on the MAC ?) <<< dont know IF that should be the problem though ...