I believe it is always hard to keep philosophy pure and intelligent from the folk beliefs that always surround us. Even today, in our scientific world, the majority of people on this planet hold and cherish the silliest possible superstititons and can't tell the difference between superstitions and science. Zarathushtra was aware of this. This is exactly why he was more concerned with getting "asha" right than with winning as many followers as possible. As Mazdaism should be today too.
And you are of course right about Gnosticism. I was discussing Christian Gnosticism and not the original Greek variety.
Thank you Alexander and Parviz for your comments and sorry I have not replied sooner, but both your posts motivated me in various directions of study, as is my habit [one thought will lead to many more - aaarrrggghhhhh], and I have been reading and studying since [in what spare time I have ], and at present I have not yet come to any specific conclusions that might further the debate here, but as is also my habit more and more questions and opinions will surface and I will undoubtedly be unable to restrain myself from offering those opinions and asking those questions .
I was interested in your assertion Alexander that Mazdaism is 'Brahmanism minus the negativity toward existance' and I would certainly agree that Zoroastrianism is more akin to the Indo-European faiths of India than the Semitic faiths of the Near East and Arabian Peninsular which were not only very unforgiving but also very exoteric [legalistic] rather than esoteric. Gnosticism itself simply means 'good at knowing', one could almost say that it is the Greek word for 'Good Mind/Thoughts'. It is post classical Semitic Christian Gnosticism that adopted much of the dualistic 'spirit against matter' attitudes that have become associated with Zoroastrianism and Gnosticism generaly, whereas the Orphic Gnosticism of ancient Greece itself was something very different and IMHO could certainly co-exist with Zoroastrianism and even seems to have had Persian roots itself.
Parviz your own post has also motivated me to study ever more deeply what the actual differences between Judaism and Zoroastrianism are and also what the similarities are and when they actually began to occur, as there are certainly some similarities, most of which [as mentioned in my OP], came about after the Jewish exile in Babylon, but some similarities are probably remnants of paleo and bronze age Near/Middle Eastern polytheism in which the Bull was a common sacred motif. Also, though many Christians and Muslim scholars would have us believe that monotheism is in some way special to them, even a cursory study of religious history will reveal that monotheism, which has various manifestations, has been a very common spiritual manifestation from Egypt to China, and the concept of the divine presence/spark [shekhina/Asha Vahishta] of God within the world is likewise a very common concept throughout human religion, so not really something that can be regarded as proof of a special relationship between Judaism and Zoroastrianism.
Any cursory study of comparative religion will discover many religious similarities from around the world which can probably be explained by man's common basic experience of god and the world around him/er. However Zoroastrians might justifiably say that Zarathustra received a more insightful revelation as to the nature of 'this' and 'that', but the question is when, where, what, why and how did that revelation become corrupted by more mundane traditions/ideas and what other traditions/ideas have a similar transcendental quality and history and/or have been influenced by the teachings of Zarathustra to the extent that they themselves have been able to better communicate with and honour God and the God within us all.