Also, pending on the SCSI chip on the SCSI card you have and the card's ROM version you will experience issues with removable media like CD ROM, tape and ZIP drives.
The GVP HC series use a Western Digital 33C93 version 02 chip (the same chip as the Commodore A2091) which is problematic with removable devices. Dig a later chip (latest is version -08) if you are experimenting locks on the Amiga while reading CD units or large partitions/HD.
ROM version can be an issue, too. Prefer versions 4.9 up to 4.15* (real latest version).
*Remembering: the "dot" in Amiga ROM versions and libraries is just a separator, like in books, and not a decimal number.
Do someone can remember if ASIM_CDFS is freeware or not? I know for sure that IDEFix97's CDFS is not.