Hi,
Are you using other (non-official) libraries which work ?
Does those files exist in your sketchbook (at the same location) ?
libraries/RGBMood/RGBMood.h
libraries/RGBMood/RGBMood.cpp
libraries/RGBMood/examples/rainbow/rainbow.ino
Maybe rename your 'Libraries' folder in 'libraries'.
In the Arduino IDE, can you click "Sketch" -> "Importe Library", does "RGBMood" appear ?
Pollop.