Yes, I think that was an error on my part. Sorry, I should have been specific that the first was with the placeholder (from the time at which I applied lightmaps). I took it from this:
A workaround is to create a pseudo cubemap by creating a white.png 64x64 square, and creating the following structure to represent a transparent cubemap
that the placeholder should be transparent. The current opacity map which replaces the placeholder has no transparency at all.
Also, to confirm that this isn't a cause, the ambient parameter in materials are now all 1. 1.0 1.0.
Regardless,
Now, the effect that runs the opacity map also contains provisions to run irradiance maps which change only indirect light, so it is possible that you changed something there which you did not intend.
That's quite possible! I found the best result with the irradiance parameter removed completely (i.e. type set to zero). It might not be so accurate, but then the Airbus cockpit having relatively large windows is very full of light Indeed.
Generally cockpits which previously have been 'open' to the lighting equations (i.e. always have shown full direct light) tend to get much darker if you only consider the light which actually falls through the windows of the plane.
I suppose that makes sense... it will just take getting used to then!