I have already explored the weight idea.  It isn't that, at least not for me.  I get this behavior even at a landing weight of 165,000 lbs and a landing speed of 129 knots.  There are other operational aspects that I am still checking out and need to rule out.  I made the changes suggested by another poster (the now famous #116 post ;D), actually one change and I will see how that works out.

One well known 737 developer had a problem like this that most likely was caused by system performance and the CS AP "problem" sounds very familiar.  When the sim would stutter, the AP would keep on turning during the time and would get all out of synch and all kinds of issues arose from this that generated a lot of overbanking and many various, difficult to reproduce and track down problems.  I had this problem until I got my system sorted out (thank you NickN) and now it is fine.  I have a feeling the same thing may be going on here.  I have very low frame rates with the CS757 in general, even worse than the payware 747, as in 10 fps or less while on approach, and I think that on approach I am having this problem.  This is what I am trying to sort out.  This would also explain why so many people are having different and difficult to track down problems with the AP whereas others are not and also has nothing to do with the CS757 and more to do with system and operation.  My own opinion anyways.  

There is an easy way to check this out.  Do an approach with the weather set to clear and to an airport that is not hard hitting.  I get about 15-20+/- fps, and most importantly, stutter and wind shift free performance, when I do this and I will check out the results with CS 757 (haven't had a chance yet).

If there are people out there who are getting 30-40 fps AND smooth and stutter free performance and are still getting this wierd AP behavior, then I don't know what to say. ;D