The Westing Game discussion

I read the book and I don't understand it. Can someone give me a clearer understanding of what went on? Who really killed Sam Westing? If the answer to the puzzle is Crow, why should she win the inheritance if she is the murderer? It is said that Westing had sacrificed his queen, Crow. What is the significance of this?

I don't understand the point or purpose of the clues. I don't understand why Sam Westing took on different identities, and why did he set up this murder mystery when there was no murderer? Turtle discovered who Sam Westing really was. How did she discover this?

Turtle tells Mrs Baumbach that her real name is Alice. But we learn that it’s not, her real name is Tabitha-Ruth. Why did she want to be called Alice? At the end of the book, Angela’s daughter’s (Turtle’s niece) name is Alice. Is this supposed to mean something?