Yep.. Vectors... And I used the Sun as the Coordinate Origin, not the Solar System Barycenter.
Try that...
We have something like this working in the new version, but it's really slow (it uses their terminal connection) and I fear it might overload their servers if we included it by default.
And Smoky Cogs?
I noticed his blog was down and offered to host it on my account, otherwise no relation.
He wrote some pretty awesome astronomy code in C# that you can find here:
http://www.smokycogs.com/blog/tutorials/astronomical-calculations-in-c-sharp/Click the 'here' link on that page (toward the top) to download all of his Astronomy code.