[bobthecabbage]

Watching your video the actuator moves up correctly but if you rev it, it should move down. If you rev quickly it will move down quickly and further than if you rev slowly.

There should be a hose going from the 'N75' valve to big air hose connected to the air filter box. Is this hose in place and free from obstruction/blockages?

The purpose of this hose is to allow air in to release the vacuum so if its blocked or connected to the wrong thing, the valve can't work properly.

The ECU operates this valve in relation to the signal from the MAF and MAP sensor, so those have to be in working order for it to function. The MAP sensor measures the boost so if its faulty or disconnected, you probably won't get any boost.