You should go to
File Coloring Rules Editor (via menu
Configuration or multicolor circle icon on the toolbar).
There you should either create new coloring profile or modify existing.
Add new rule, set parameters to e.g.
Field: Full filename
Match: Is
Value: Benny Hill
Then choose font styles and colors. Create as many rules as you need.
Save changes and then activate appropriate profile via multicolor circle icon on the toolbar.
Unfortunately, you can not create a rule for zero-sized folders. Unless sometime Mathias add plugins' specific actions to the field list or
Script type which would use user script