For Pro Tools & 32 bits, you'll need to check their docs.
That said, if you start the task manager and find the Pro Tools process, if it has a *32 next to the process name, it's already running in 32-bits.
Okay, here's the patch you need...
Reason 3.0.4 won't rewire without that...
I know, because I tried for hours until I found that.
If you install the patch and still have problems, then download the 32-bit version of Reaper, as I can help you rewire it with Reaper to see if might be a Pro Tools issue.
I don't have Pro Tools, so that's the best I can do.