As I am also using Rosetta Stone Japanese, I understand the need for occasional translations using words rather than pictures.
It is sometimes difficult to know what exactly some of the pictures are trying to represent and say, some pictures can practically have many meanings, and I find myself looking to a Japanese dictionary or online to double check the meaning of a word or certain forms of words that a picture alone cannot describe.
I do find Rosetta Stone helpful and fun to use as a interactive learning media, but language books and, even better, person to person, is also needed to learn a new language.