I too am not able to use the V6 and my Nissin i40 in TTL Pass Through mode with my X-T1. I have 4 V6's and would love to exchange just one for one with a new hot shoe. I have tried everything but I am only able to fire it Manually while connected to the V6.
If you could spare 2 weeks without using one of your V6 then send it back and we will replace it for you. The replacement process is finished in a day so we usually ship the unit back the day after first receiving your package. We use E-Express from our post office and there are daily flights so delivery is pretty quick. Let me know what other concerns you may have. Thank you!
Hello @marcelBoth V6 and V6 II uses the same top and bottom hot shoe. So in terms of mounting it on the X-T1 there should not be any difference. AF-assist as you indicated is indeed a camera-led function. So there's no way we could "Forced" the AF-assist like we did for HSS Thank you.