I own a mixpre6 which records in polywave files of up to 8 tracks.
I never remove the sd card from the machine and use a usb-c cable to see the data on the card through my macbook pro.
Using the wave agent application I can manipulate the polywaves into whatever configuration of files I want. 1, 2, 4, etc track files are easily created from the data on the card.
I just don't understand why anyone has a problem with polywaves.