Question for the Minimig (now MiST) experts out there

I'm new to the MiST configured with Amiga AGA. I just received my system a week ago and before I start making full use of it I'd like to make a master backup of the SD card with the Amiga configuration I bought with my MiST.

Is it possible just to copy the content of the original SD card in a new SD card formatted in FAT32? Can I use a bigger capacity SD card, i.e. 32GB with FAT32 format? The reason I ask this last question is because I already tried using a 32 GB SD card and the MiST can't read it, so I am not sure if this is the issue.

The original SD card that came with the MiST has folders and files, including the cores and 3 hdf's images with Workbench configurations.

Thank you in advance for any help.

Here is an update also posted at minimig.net:
For some strange reason either straight copying or creating an image using Win32DiskImager is not working for me. I have use Windows Dos' diskpart to clean and format the 32 GB card in F32 and SDformatter, but in either case: No luck.

The MiST can't boot from the image SD card.

Any other suggestions?

Looks like it probably needs to be repartitioned using RDB and an Amiga filesystem. I'd try using WinUAE to do that. It's possible that using "dd" (linux command/program) could clone it.