Zesterer's Volumetric Cloud & Mist Mod for OpenMW: starting the game with clouds enabled in an interior cell makes everything black
If you have the clouds
shader enabled and you start the game from an interior cell (like when starting a brand new game) everything will be black. Going to an exterior cell and then back to the same interior cell will fix it and from now on interior cells won't be problematic anymore. The workaround is to disable the shader (or post processing) if you start the game in an interior cell and re-enable it once you're in an exterior one.