Ah ... it has been moved to here All and Everything ... so write what you wish.
There is no connection. Both were also "young" in the West and I remember Bahais used to be very happy to work with the BKs. In the West, they are both very strong in working the Interfaith and United Nations world. Probably both groups thought that they could convert each other ... or that some Bahai or another "must" be a BK.
To the best of my knowledge, I met with them as a BK, Bahais are a sort of Shiite Islamic revivalist movement, in the nicest possible way. Yes, they have MANY times more followers, 5 to 6 million, and even better and more expensive real estate and architecture. They have a fairly 'stock in trade' story for the Judeo-Christian-Islamic tradition ... persecuted leader reacting against injustices of corrupt rulers, genuinely persecuted followers [they dwarf and put to shame the BKs' advertised "hard times" (tm) in that sense], loveful impression of a single God.
Bahá'ís do not expect a new manifestation of God to appear within 1000 years of their founder's revelation and have a "Cycle of Fulfillment" began with the Báb that will last at least five hundred thousand years ... with numerous Manifestations of God appearing throughout that time.
So may be Lekhraj Kirpalani picked up the 5,000 year cycle off them. May be in his mad phase, something he had heard once came back out again and became Gyan. Interestingly, the Bab had one main female follower who was given the title of Táhirih (the pure one). He also wrote mad letters to Queen Victoria and so on ...
so may be Dad was copying what he read or heard of Bab and Gyan is not quite that unique after all.
The Bahais have an excellent and practical administrative system, court etc which ought be the envy of the BKs. In this aspect, the BKs look particularly cheap and amateur.
That is my "starter for 10". The BKs could learn a lot from them. But I also found that they did have quite a few spiritualist superstitions, e.g. purification with salt etc.