I didn't vote, but I will try to explain. I would pay for the book if:
1. It would cover EGSL in 100%.
2. It would cover Lua for EGSL users.
3. You would decide to focus on EGSL and take it more seriously (I mean no text like "Calm down, I have life after EGSL and almost no time for coding" etc).
EDIT: Don't get me wrong. I'm not trying to tell you what you should do. I'm just saying what I'd expect if I paid for the book.