egwpisteuw wrote:I don't have the specific answers to those questions but I can tell you that if you can read the NT in Greek proficiently, you can read the Septuagint.
I agree - in fact, the majority of the Septuagint is probably easier because the word order is less complex (at least, that's my observation.)
If you are interested in reading the LXX start with the smaller books like the apocryphal Daniel stories, Susanna and Bel and the Dragon. They're great stories and easy reads. I just posted a reading aid that takes care of some of the more obscure vocabulary in Susanna:http://www.greekingout.com/lxx-reading-aid-susanna/
Bel and the Dragon should be finished in the next couple of days. Not sure if it's exactly what you're looking for, but maybe it will be useful to you.