I did not follow Steorn's Orbo closely and do not know what you mean by that.
What was the error in their interpretation of their results?
It’s a long story. I was speaking of the Steorn’s motor. I recall the alleged principle: rotating permanent magnets are attracted towards the ferrite cores of toroid coils on a stator. By suitable pulses at the right time, the saturation of the cores reduce the permeability, and so the magnetic force when the magnets move away from the toroids is weaker than when they move forward, giving a net energy gain. As the energy for saturating the cores is presumed to be independent of the energy involved in the magnetic attraction, it could be less, giving OU.
Steorn calculated the useful electrical energy for pulsing the coils: it’s the provided electrical energy minus the Joule losses in the resistance, minus the “iron loss” in the ferrite, minus the difference of energy stored in/recovered from the inductance between the start and the end of the pulse if the inductance has changed in between due to the change of permeability.
Steorn knew the coil resistance, inductance, they measured the “iron losses” in the ferrite, and so, they could say that once you have removed the losses, the useful energy provided to saturate the ferrites is less than the energy that rotates the motor.
The mistake of their measurement interpretation consisted in having taken into account among the losses, the useful energy!
When a permanent magnet approaches a ferrite toroid, the magnetic flux penetrates it and loops through a section of the toroid. When you pulse the coil, the flux from the coil in this section superposes to the flux from the magnet. They add or subtract, depending on their relative direction. The flux becomes no more uniform along the whole toroid, and so is also the permeability. The toroid is no more toroidal from a magnetic viewpoint. The coil flux being conservative, this means that there is a flux leakage outside, around the section of less permeability (I can develop this point is necessary). This outside field is the magnetic field that powers the motor at the price of the Lentz law that applies now due to the toroid partly open.
From the viewpoint of the measurement, the “counter-voltage” from the Lenz law is not distinguishable from an iron loss and so, Steorn counted it as a loss instead of the real energy for rotating the motor.
Nevertheless their motor has been instructive for me, when I discovered that the saturation of a ferromagnetic core applies only along the lines of the saturating field:



In other words, this means that to saturate a material and for the saturation to have an effect on a controlled flux, the controlling flux must be colinear with the controlled flux. Therefore the sources of the two fields are coupled and interact with eachother. The work done to control the direction of the magnetic domains by the saturating field opposes the work done by the controlled field, the laws of conservation (momentum, energy) and Lenz law apply, as in all other parametric devices.