FFS needs a lot of RAM to initialize a partition. You should count ca. 1 MB RAM per GB harddisk space. So if you don't have at least 4 MB RAM you won't be able to format a 4GB partition.
SFS is irrelevant because it needs a 68020. It does not run on an A600 without accelerator. SFS\0 is the right identifier for SFS. SFS\2 is experimental support for partitions bigger than 128 GB.
PFS fails for install for 68000 if you select to install pfs3ds because pfs3ds for 68000 does not exist in version 18.5. Only the original 18.3 CD contained it.
To access anything outside the first 4GB of the harddrive you need a patches scsi.device, too. This will eat up another few KB of RAM. Dividing the harddrive into a lot of 4GB partitions does not help. All these partitions will write into the first 4GB of the harddrive, corrupting each other.
IMHO using such a large harddrive on an A600 is overkill. You should go for a 4GB CF card, then you don't need to care about limits, patched drivers etc.
