download fat95 from aminet, there is some explenation/dosdrivers there that might help.
and fat95 is more compatible with fat filesystem's than crossDOS ever was, you also have msd95 which is very good for simply connecting a hd, it's read-only but is far simpler to use, for instance
type this into a shell
1> msd95 -d -l -nscsi.device -u0
this will attempt to mount any hd formatted with FAT on the scsi.device using scsi commands with unit 0
if it succeds you will get a drive icon with the partion/hd name just as a normal amiga HDD, to quit you simply press CTRL-C in the shell, then it will remove the HDD etc.
msd95 seem's to be slightly more compatible with diffrent FAT's than even fat95 is.
then you have the utility giggledisk to try, it will attempt to mount any FAT, EXT2, EXT3 and NTFS (probably also FFS :-) ) that it can find on a specified HDD/partion etc (haven't used it much so...)