i've had this only about a week, but noticed the estimated rainfall has been incorrect for my property a few times now and it did not water the next day. Today it says that we had .65 inches rain when we did not get any.  

My suggestion is a rainfall bypass of some sort.  On a day where it predicted rain and did not, maybe a 'it did not rain today' bypass  button so that it knows whether you in fact got rain and schedules accordingly.

i have a bonsai greenhouse that depends on daily water on one of my zones.  I activated NOAA as well as FAWN in an effort to improve accuracy.

we can use some way to correct it if its wrong for your property rainfall rather than a broad area rainfall.