I skimmed over the thread and may have missed what I believe to be the problem.
If you are using Rapid-fire with WU, not all of those records are saved. I am not sure what the criteria is for storing a new record and it seems to store the data every 3 minutes or so.
Your software will then need to maintain the gust value in order for it to be captured. The typical definition of "wind gust" for personal weather stations is the highest wind speed over a 10 minute period, either by using a single "wind speed" from the station or a combination of "wind speed" and "wind gust" reported by the console.
In WUHU I take the highest value of whichever is available (one or both) and retain that gust value for 10 minutes. In theory, no matter what scheme is used to store the records at WU, the gust value should be captured one way or another.
So this comes down to the software you are using and the way that gust is reported to WU.
If you can demonstrate that your software is sending your missing gust value for a period of 10 minutes (capturing the URLs sent, not local data in a database or chart), I will contact the guys over at WU myself to look in to it.
Thanks.