At the moment, xpra supports this on the server: the xpra server stays alive even when shifter_server is stopped.
Ideally, we want to keep all the sessions running and just re-load the session files when the server re-starts. The problem comes from the fact that NX writes to stdout and we watch this output to get the current session state, we will need to redirect to a file instead and watch that (and maybe also start it with 'nohup'?)

When starting the application on win32, we get what looks like a fatal error (it is not):

The application has failed to start because libgio-2.0.0.dll was not found. Re-installing the application may fix this problem.

This is bogus, the application is fine, it is just something to do with gtk pixbuf loaders (svg?)
We should at least prevent this error from coming up, ideally we should find a proper fix for #10 (SVG support)

The error report is totally useless (thanks Microsoft), and according to ​this response to my question on the py2exe mailing list, the only way to resolve this is trial and error. (great..)