Some more news.
BenQ appear to have located and fixed the issue within their SDK!
We now have an internal test version of LightSpace using the new SDK, with updated BenQ firmware in the PV270, and all seems to be working as it should...
We hope to update the release of LightSpace with this new SDK in the coming week.
Any BenQ PV270 user will also need new display firmware from BenQ.
Note: According to BenQ only the BenQ PV270 display has suitable 3D LUT capability, so is presently the only BenQ display that can be calibrate with LightSpace.