I do not know much about bookit, but I assume you are wanting to learn an
opening repertoire and I have a suggestion.
When I learned my openings, I put them in SCID in pgn format while i went. I
also have saved the positions as positions in winboard to play against chess
engines. This seems like a lot of extra work, but it makes you actually do the
moves in the opening at least twice. It is also good because you may analyze
deviations from the book and add it as you go.
Also, is good to play the position against the computer until you dont lose
material anymore. I gave each move in my repetoire a ! and loaded it as a book
for yace. Then, yace plays only the openings you are supposed to have already
I "upgrade" my openings each time i play a line that i dont end up on familiar
ground. You then have three good ways to practice openings. Can run through the
pgn file you have made, load a middlegame position you want to practice, or
have the computer play a random opening you should know.
Also, over time you can add more depth to your repetoire by choosing what you
might deem the "main line" in your middlegame positions. I even sometimes save
any "great moves i find" into my DB.