photos taken in raw format in xt 3 using lexar 128 gb card are not transferring to Mac air where as jpeg files are transferring without problem. please help with advise. recently updated to  xt3 firmware version 5.   

Well, I upgraded my firmware last night to V.2.00 and guess what? The PRE-EF is now available. I have absolutely NO idea why I couldn't access it before. Thanks for your help. I am really excited to be a real photographer again! This forum is such a great resource and I know that I'll be availing myself of the combined wisdom of the Fujifilm community many times.

sorry, I was wrong, according to the manual PRE-AF works only in ES (electronic shutter mode ).  I set my Xt5 to shutter type M+E, that works.  menu camera mode 1/3 last item, hope it helps.

I use the same as I always done, but it would be fun to hear others thought and settings. I think it depands on what type of street photography one shoots also. I shoot a lot of sun and shadows were the person is more of an extra to the actual scene. So I use AF Mode (Zone) and Custom settings I never really bothered to play around with.  So no idea why I settled with this but I go with tracking sens. (3) Speed tracking (middle) and Zone area switch (front). What's your settings and why, also what type of street photography do you shoot?

I'm not sure what you mean by "high speed mode." I did a User Settings Reset and returned the camera back to as it came out of the box, in case I changed something by accident that prevented me from getting the PRE-AF option, but it's still greyed out. Obviously, I'm missing something. I'm not even sure I want to enable this setting, given its impact on battery life, but now I HAVE to solve this mystery.