Skirmish against AI ?

Does anyone know if it is possible to play a skirmish 1x1 vs AI like in BFGA1?

Yes, that is possible. In the "battle" menu, just click 1 vs 1 skirmish, select a fleet and your abilities, and when you start, you can then select what kind of enemy you want to fight against.

Great :), thanks a lot! And welcome Tyranids ;)...