Thanks @Menithal, this does look like an older graphics card support bug. No, not integrated graphics. For that to work on an integrated graphics system you have to hack interface to permit OpenGL 4.0. This weird shadows issue is likely related to the other problems: point source lighting damaged, running with shadows disabled damaged, sparkles with shadows disabled, etc. @Sam was looking into it, though I suspect he’s stopped. Eventually, I’ll get a newer system, but it does leave a lot of people who want to try out HF in the lurch.
The skybox color is not affecting shadows much. its the ambient lighting that does, set to white. Presently I have ambient level at 1.3, azimuth at 0 degrees, light angle at 61 degrees.
Also, I am not having any problems with my system in sinewave Space, where I find myself nowadays more than here in HF.