The spacecraft don't seem to have a floor plan that would support spinning around their center of gravity and walking around inside of them, plus they're too small to do so without causing motion sickness (if they were to spin at the required rate for substantial simulated gravity)...
However there are two ways that you would be able to realistically generate simulated gravity, although due to the maximum speed in the game being set only one is viable. The first way which is not viable is simply to lock the same thrusters used for vertical takeoff and landing to a on position, this would create a linear simulated gravity in the whole spacecraft because it would continuously accelerate and gravity is just simulated acceleration (can't be done for more then a few seconds in ED because the spacecraft would hit a predetermined max velocity). The second way is to do the same but also fly in a circle with a fixed tangential velocity forward so the maximum craft velocity is not reached, this is like spining the spacecraft but you are moving the axis of the spin outside of it. Both are only viable in the ED universe due to the high specific impulse that the spacecraft have (in other words they can afford to burn a lot of fuel) .
