John, thanks for the more precise directions (yesterday I gave up in confusion). To encourage other mac users to switch, 
here's the exact url:

ftp://ftp.smalltalkconsulting.com/experimental/64bit/32bitImage*64bitVM/Squeak%2064-32%205.2b2.app.zip

I've made this my default vm and so far so good (I can open and operate a bunch of my images). I'm looking forward to 
apple-Q, apple-H etc working.

Thanks for the shiny new vm!
-Simon