An "advance," in the context of a book, I believe means a sum of money paid to the author before the book is even written. The phrase "lacks any zip" does not seem to make sense in this passage, which appears to have been written by a non-native English speaker. It apparently should be "doesn't lack any zip," that is, it doesn't lack pizzaz, it's entertaining.
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NL8881) Does advance mean advance payment?Yes, it does.
NL8882) What does "lacks any zip" mean?does not have any [vim / vigor / vitality / verve / pizzazz / energy / life / spirit / excitement]