You must have one-light/dark-ui/syntax theme activated for this package to work. It will change the hue of the ui/syntax according to the current project name.
Main brightness and saturation values are configurable. Base hue could be changed if the project -> hue mapping doesn't suit you.
You will have to change the default values if you use the one-light theme. Base values for light theme are :
This package works by creating copies of the original one-dark-syntax theme and virtualy changing the current theme. This makes the configuration and the first project launch a bit slow.
Good catch. Let us know what about this package looks wrong to you, and we'll investigate right away.