There is not much documentation in English for now. Feel free to help if you want to !!

• A short introduction to Lexique codes
  New. B.(2003)
  MSWord

• Lexique 2 : A New French Lexical Database.
  New, B., Pallier, C., Brysbaert, M., Ferrand, L. (In Press) Pdf
  Behavior Research Methods, Instruments, & Computers

Check also the french documentation part. It can help !!