Hi
streetking,
You could go through the AWA template at the forum by ChineseBurned.
This template will give you an idea of how the essay must be written.
IMO, the AWA is simply an extension of CR(since you have to talk about
the assumptions the author makes and critique with examples)
As for the IR and AWA preparation, I would suggest you to take it in every test
that you take while preparing for the exam.
A good resource for IR:
https://www.gmatpill.com/ebook/GMATPill-IR-EBook.pdf It definitely makes sense to spend maximum possible time on Quant and Verbal
but in the process don't ignore IR and AWA!
Hope that helps you!