Originally Posted by n0ahg
From the support section of this very site
"1. Select the Reason application.
2. Select "Get Info" from the File menu in Mac OS X.
3. In the Info dialog, tick the "Open in 32-bit mode" checkbox.
When you now launch Reason it will run in 32 bit mode."
After hours and hours of the same problem not being able to get Rewire to engage in Pro Tools HD9 with Reason 7 this post saved me. Geez. This is worthy of a sticker or something on the upgrade packaging. What a STRANGE solution. Thankful to be up and running. Reason 7 will probably be my last propellerhead product. Reason 3 stopped working with my snow leopard so I stopped using it. Finally upgraded to 7 only to realize i would need to upgrade to Lion. Always frustrated with these products.