i found something
7 rays : https://en.wikipedia.org/wiki/Seven_rays

...Blavatsky summarizes the syncretistic principle of her doctrine as it relates to the seven rays:

"...a key which reveals to us on indisputable grounds of comparative analogy... the Indian phœnix, the emblem of cyclic and periodical time, the "man-lion" Singha, of whose representations the so-called "gnostic gems" are so full. Over the seven rays of the lion's crown, and corresponding to their points, stand, in many cases, the seven vowels of the Greek alphabet AEHIOYW, testifying to the Seven Heavens. This is the Solar lion and the emblem of the Solar cycle, as Garuda is that of the great cycle, the "Maha-Kalpa" co-eternal with Vishnu, and also, of course, the emblem of the Sun, and Solar cycle. ... As well remarked by C. W. King: — "Whatever the primary meaning (of the gem with the solar lion and vowels) it was probably imported in its present shape from India, that true fountain head of gnostic iconography." (Gnostics, p. 218)[34]...

Letters :  AEHIOYW = A9 in base64
this explains why 7x9 chessboard is used instead of 8x8 chessboard

A9 square may be the white square A1 in original picture if you don't rotate , maybe there is a flower on it ( maybe a lotus ?? )

2nd hint : it's about the twin flame
In 7 rays , 3rd ray's wisdom master is MahaChohan ,  this truly Great Lord is called the Keeper of the Flame.. His twin flame is Pallas Athena, Goddess of Truth. ?
https://www.summitlighthouse.org/maha-chohan/

Sorry 4 my bad English , i am from Viet Nam but very enthusiasm in solving this puzzle