My tips for AWA. Thought it might be useful to save time for the GMAT takers who may not to unnecessarily burden themselves with the AWA stuff
First lets start Analysis of an Argument.
99% of the time, if not 100%, I preferred to disagree with the argument. The reason for that is that the argument will use one scenario and jump to conclusion(s) based on the scenario. Now if you are good in CR, then you know that several external factors can strengthen or weaken a conclusion. Use the same concept here. Bring in points that would weaken the conclusion. Pick out the inherent assumptions in the argument and clearly explain that those assumptions are generic and sweeping. The idea of Analysis of argument, in my opinion, is to gauge how you are able to pick an argument apart and logically prove that the conclusion will not hold if the external factors are considered.
Now lets move on Analysis of a Issue. Here you have the flexibility to agree or disagree with the author. Whether you agree or disagree state the reasons for the same. Explain every reason with a good example. Then acknowledge what the critics may say too. After all the critics of your idea also have some valid points to present. Finally conclude saying that even though the critics have some valid points, the benefits arising out of my points far outweigh the benefits arising out of the critics' points.
Hope this helps