I have been working on a project that involves eConnect 10 for Microsoft Dynamics GP 10. The documentation exists, but is very sparse when it comes to specifics about using the interface.
When using the RM transactions and distributions, the first bite that we had was that there is a property in the taRMTransaction called CREATEDIST and by default it is set to 1 and you need to ensure that it is set to 0 if you are creating your distributions yourself, which in this case I am.
More to follow on the process of this so that there is at least some documentation on the web about how to do it entirely.