OpenRA

Does anyone know what the controls are? i started playing but i cant figure out how to build a structure.

System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
at Tao.OpenAl.Alc.alcOpenDevice(String deviceName)
at OpenRA.OpenAlSoundEngine..ctor()
at OpenRA.Sound.Initialize()
at OpenRA.Game.Initialize(Arguments args ...