Apple Logic Pro /LogicExpress Discussion

HI,
I posted this on logic-users forum originally. It shows a few of the questions I have about 
'digging deeper'.

Does anyone know the exact differences in dithering options in Logic (Express)
7.1? That
is, is Pw-r 1 (etc) recommended for certain music styles?
Also, there are features I am unsure about, and no book I have seen
addresses....
example... audio energizer. Is this a loudness maximizer?
Is there an advanced book for Logic Express users? For example, the advanced
book in the
Apple training series (by M. Sitter) seems targeted at Logic Pro only.

Mark