The main change is System.Diagnostics.Trace and System.Diagnostics.TraceListener doesn't exist in Monotouch so I wrote 2 'fake' versions of the classes. The other change was to the compile has to use the already definied _WINCE_ so the web stuff isn't used.
Apart from that, it's just the inclusion of a Monodevelop format project. I'm not sure if you build a Monotouch binary on Windows it will work on the Mac, as the PE header might get in the way.
I'll upload a patch with the 2 changes + csproj file later, and also try compiling on Windows and referencing on the Mac.