QUESTION: Elaborating on your post, A Weird Truth About Sidereal and Tropical Systems; Another problem is that stars move around Galactic center and are not fixed wrt each other. So, is ayanamsha inherently subject to flaw?

Yes, but this is relevant only to extremely long periods of time. For example, observations made accurately 100,000 years ago will not seem accurate today. So, an ayanamsha that was accurate then will not be accurate now. However, this is why Astronomy texts request their readers to master them and periodically update and correct them. Our current Version of Sūrya Siddhānta, for example, says that it is not the original version, it has been updated (probably a few times between 12 and 2 thousand years ago).

But still I do agree that this is an additional factor explaining why sidereal measurements are inherently blurry.

QUESTION: There is also a problem of whether polar coordinates are used (which i think is right). I don’t mean Ernst’s polar coordinates to equatorial plane. I mean polar coordinates to ecliptic plane – ie perpendicular drawn from star to ecliptic plane.

This is another significant problem, I agree. As far as I can see, Sūrya Siddhānta undeniably uses the polar perpendicular. But I specialize in astrological interpretation. My specialty is not astronomy. Really we should see what learned astronomers opine here. However, as far as I have seen the problem is (A) there isn’t a big urgency to research this, not the kind of urgency that would provide the funding and coordination required, and (B) those who have researched it therefore have done so rather quickly and come up with different conclusions.

QUESTION: I remember you saying nakshatras are abode of Gods however these Star fields are also calculated just like Rashis. We get one and follow 13’20” to get another and so on. These can’t be bound to Yog tara as they move which i mentioned in para one above.

The Vedas say the gods dwell in the nakshatras. They also say the function of Nakshatras is to measure passage of time. They also say that time is the shakti allowing karma phala (ie. allowing actions to create effects). And finally they also say that the gods oversee the universal laws and properties that ensure relatively consistent effects from actions. This is a very practical upshot of what they mean when they say “the gods dwell in the nakshatras”, and many other things that sound superstitious to many ears. Really what they are saying is very empirical and logical: “without time, no change occurs – hence no action causes any result. The laws of the universe describe how actions cause results. The gods are, in a practical sense, these laws. The nakshatras are, in a practical sense, time.”

Coming to what you said above…

You protest that since the nakshatras are calculated like rashi they cannot be abodes of the gods. I don’t see any logic in that.

You protest that they are 13’20” uniformly, so they cannot be bound to particular stars. There is also no logic in that. For example, Sūrya Siddhānta says things like “Citra-tāra (the star) is exactly in the middle of Citra Nakṣatra (the star-field, the star’s zone).” and “Revatī-tāra is very near the end of Revatī Nakṣatra” etc.

In fact some of the yoga-tāra are OUTSIDE their ecliptic field! In that case they will say things like “Such and Such star is x number of degrees east/west of its own border.”

Finally, you protest that since the stars have their own slight independent motions these statements like “citra-tāra is in the middle of chitra-nakṣatra” cannot be permanently accurate. I have already replied to that: these statements would be updated every catur-yuga. There are also destructions and recreations which would rest conditions.