If you are using flex daily unfortunately we haven't built a calculation to show water savings yet. We have a few ideas which are all fairly complex to implement. Any ideas regarding this appreciated!
Regarding the weather station, you can view precipitation on the soil moisture graphs (details) assuming you are using flex daily. If it is not showing up we will need screenshots of the missing data and a screenshot of the weather station reporting the precipitation so we can provide the data to our weather provider.
If not flex daily we would perform rain skips which show the precipitation information in your activity feed. If this is incorrect we will need a screenshot of that and weather station reporting to provide to our weather service provider.
Hope this helps.