Just in time to set up ISS for tomorrow's Cygnus launch.
Edit:
First of all, it is not working at all for me, so I have not been able to try it. I have .NET Framework 4.5. I suspect perhaps that my virus program is blocking it.
Anyway-
I read in the manual that there is a 50-100 km error.
Are you using the SGP4/SDP4 orbital model to propagate from the TLE Epoch up (or back) to the simulation time, or are you just copying over each element from the TLE into Orbiter
as is. The latter is a
no-no, see the Celestrak FAQ #5:
https://celestrak.com/columns/v04n05/index.asp#FAQ05
I recommend that you check out Ajaja's Scenario Editor TLE:
Scenario Editor TLE
Being able to automatically sync with the Celestrak databases would be useful, but if you aren't using SGP4/SDP4, then I am going to stick with Ajaja's solution.