The book itself as well as audio lessons are completelly organized and presented in very simple way, easily inteligable.
I am also a non native English speaker, but have no problems so far.
Anyway, I am at the moment in Sarajevo, Bosnia and I do have some peaces of the book translated for my own use. If this can help let me know. Up to this point I am not aware of any authorized translation into Bosnian or Croatian language. It might be of interest to you to have a look for a photoreading school in Zagreb whose methods have many common points with this program.
Cheers/
Vozdra iz Rajvosa
Irfus Somnus