Hmmm. There are a number of other tags with "." in that config file. If you aren't in a hurry, you could just wait for ExifTool 9.45. But to get this working now, you just have to add the Name definition to all necessary tags. For example, change
'Spatial.Quality' => { },
to
'Spatial.Quality' => { Name => 'SpatialQuality' },
in your config file.
- Phil