Neilsio,
I am not sure what
http://wtc.nist.gov/NISTNCSTAR1-6D.pdf fails to explain.
At which point, sequentially speaking, does this break down for you?
It may be that you don't understand some of the technical jargon. If you can explain what you dont understand, or disagree with, then we can explain it to you.
This gives an extremely detailed sequential analysis of the collapse.