Tengah
I still cannot recall why the name Bruno Szota is familiar to me. The training in Karachi was mentioned by another airman from the group, who mentioned that they initially had to go to Burma or China, but were recalled to the UK. This is a misty part of the story, as I have not found any documents on it. Without doubt there were talks with Chiang about forming Polish units in China, but they ended with nothing. IIRC there were about 70 airmen in the group. They went via Persia and Iraq to India, where they boarded the ship.
Re Enigma
The Poles were simply not wanted at Bletchley Park, so they took up the French offer and worked in unoccupied zone of France intercepting German messages. Their most important achievement was use of probablity theory to decode messages, and creating decoding machines.