I have the old Logomatic 2.3 working with the new SDHC USB bootloader. At first, FAT32 was not enabled. because the mass storage part doesn't even need a filesystem driver, the host takes care of it. However, In order to find and install FW.SFE, the bootloader needs FAT32 however, so this version has it.
Also, the old Logomatic firmware has been updated the minimum amount to use SDHC and FAT32.
All of this works for me, and generates log files, but it sometimes takes a LONG time to mount over USB (sometimes a minute or more).
So now I have put my code where my mouth is.