Hi mozzwald, you want a debug? That requires effort on my part. So prior to my reading your response, I took the other approach and simply rummaged through all those micro SD cards I have in all those IoT devices and started checking what would work and what would not work. Here is what I have found thus far.
Transcend SD cards do not work in my Fujinet in any size and still no joy after adjusting allocation unit settings.
Sandisk SD cards - 8, 16, and 32GB work out of the box on fat32. This is clearly a safe bet for use with the Fujinet 1.3
PNY SD card - 16GB works out of the box on fat32.
In my case the Sandisk card(s) resolved my issue and I will just throw that in as a compatible card for use. Only had the one PNY card to test but it offered positive results as well. I hope this helps others who come across this issue.