The volume sliders on the options screen do what you'd expect, except I can't seem to turn down the SFX volume at all. Even with the "Master" slider at 0% they're at full volume.
With the graphics settings I have sort of the opposite problem: all the checkboxes are inevitably filled when I return to the options screen, though they do seem to take effect (even if I can't make out any scanlines; it just gets blurrier).
I do click "Save Settings", of course...
The game can and does write successfully to $XDG_CONFIG_HOME/unity3d/Red Phoenix Studios/laservasion.