If you download the Standard Vassal module (Epic module if you want create special epic scenarios), you have all what you need, including all current available Units (austrian and prussian are following, AFTER they are published).
If you have special questions, you should catch me direct online on Vassal,
i am most online with the CCNapo module
Ok, now i saw your mistake
you used the "Scenario-Editor"
This Editor is a simple Vassal module without the possibility, to play online
Therefore it´s better, you use the "Game-Vassal-Modules", because you can setup scenarios with it much better and you have additional maps, units and Terrain.
And same setups you can then use also, to play online