I updated the Tibetan Calendar for the Water Dragon Year adding Naga offering days and showing bad days to raise prayer flags. You can download it from my website
. It is still packaged as a zip file for now. I have not been able to find hosting for it just as a JAR file yet. If you don't know how to unzip files, then I can email the calendar to you (but under Mac and Windows you just double-click and should extract it immediately, possibly to a temporary directory - you would then move it to your desktop or wherever you wanted it to reside).
I used multiple sources for the Naga days and prayer flags days. These aggreed with each other except for a few days. When a discrepancy arose I took the more conservative rout. This added a few bad days to raise prayer flags and in three cases turned a good day for a Naga offering into a bad day (this happened once) or a neutral day into a bad day (this happened about twice).
I'll get the Rigpa calendar shortly and see what they say.
So my sources are the Nitartha published calendar for 2012, the "Naga Serpent Spirit Puja Days From Tibetan text kLu Thebs dang Phan Yon bCas bZhugs so" pdf that Greg sent me, and data from Saraswati Bhawan, especially their "Du-Khor Be-kar Naga days according to the astrology of the Kalachakra, which is based on the Yajurved" that Ngodrub sent me.
I still need to add Parinirvana days and birthdays.