@Thomas: at the first picture, under the filesystem section, it's written: DOS\07
This picture only shows the identifier (DOS\7) it does not say whether this identifier has an actual program connected to it (L:FastFileSystem 51.10).
at the boot ffs partition, check the long filenames.
DOS\7 *is* "long filenames". That's the difference between 3, 5 and 7: 3 is international, 5 is directory cache and 7 is long file names.
Could the whole drive, including the boot partition, be set up with PFS3 as I use that in my IDE drives?
pfs3ds could work. pfs3 (not ds) does not work on partitions above the 4GB border.
PFS3 is 68k after all. For OS4 you should switch to SFS which is PPC native. (But you still need the 68k version of SFS in the add/remove/update section, just like FFS above.)
Bye,
Thomas