Hi tr123,
First off, raising a 410 to a 590 is a significant achievement - and it shows that you have the capacity to learn, adapt and improve. The jump from 590 to 740 will be a bit more challenging though - and you will have to focus on practicing Tactics and eliminating little mistakes from your work. Thankfully, the GMAT is a consistent, predictable Exam, so you CAN train to score at a higher level.
Given the similarities in your CAT Scores from Sept. 27th and Oct. 7th, there is a reasonably chance that you have gotten 'stuck' at this particular score level - and you may have developed some 'bad habits' during your prior studies that are keeping you from scoring higher. Besides taking a practice CAT, what type of study routine have you been following over the last several weeks? Are you following a specific study plan or are you just working through random GMAT subjects?
In addition, "review" is an exceptionally important part of the GMAT training process; your ability to define WHY you're getting questions wrong is essential to defining the areas that you need to work on (and the specific things that you need to 'fix'). As such, I'd like to know a bit more about your last CAT. While a full Mistake Tracker would provide a lot more information, there are some basic questions that you should be able to answer (and the more EXACT you can be with your answers, the better):
After reviewing each section of this recent CAT, how many questions did you get wrong....
1) Because of a silly/little mistake?
2) Because there was some math/verbal that you just could not remember how to do?
3) Because the question was too hard?
4) Because you were low on time and had to guess?
5) How many Verbal questions did you 'narrow down to 2 choices' but still get wrong?
GMAT assassins aren't born, they're made,
Rich