trouble reading linux loopback files in FreeOTFE

Results are very mixed trying to share encrypted loopback files with
FreeOTFE. Files were made under linux, both Fedora Core 2 (FC2) and
Fedora Core 4 (FC4). They're tested-- they can be re-opened and read
on the platform where they were built, plus FC2 and FC4 can read each
other's aes, twofish, blowfish, and "none" files, but not one
another's "xor" files for some reason. For the acid test, getting
FreeOTFE to read, them I follow guidance at
http://www.freeotfe.org/docs/Linux_e...cryptoloop.htm.
Issues:

1) FC2 vs FC4 differ a little
- have different set of crypto modules
- can't cross-read each other's xor-encrypted files!
2) losetup syntax in FreeOTFE's instructions differ from what's legal
under either of my fedoras
- have different encryption-specification keywords - FreeOTFE uses
e.g. "-e AES128" and "-e AES256" which fail in linux, which wants just
"-e aes"
- shows options -H and -S that losetup in Fedora doesn't support
(not in man page, fails on command line)

3) bottom line, can't read most of the files under FreeOTFE
- either FreeOTFE doesn't/can't decrypt them the same way my versions
of losetup encrypted them, or the instructions don't match the way my
versions were encrypted and I don't know which exact FreeOTFE
parameters do (there are so many combinations!)


Results

FreeOTFE can read the loopback file with "none" encryption produced by
either Fedora.

FreeOTFE can read the loopback file with "xor" encryption produced by
FC2, but not FC4.

FreeOTFE cannot read the loopback file with "aes" encryption produced
by either FC2 nor FC4, using either the instructions for "128 bit
AES" or for "256 bit AES"

FreeOTFE cannot read the loopback file with "twofish" encryption
produced by either FC2 nor FC4.


Any help or related experience please??


------------
I made all my (ten) test files by running the script below:

#!/bin/bash

PLATFORM=FC4

#./loadmodules

# must use "1" in losetup, not "xor", for encryption designator
LIST="none:none xor:1 aes:aes blowfish:blowfish twofish:twofish"

for ENCTYPE in $LIST ;do
ENC1=`echo $ENCTYPE | cut -f 1 -d ":"`
ENC2=`echo $ENCTYPE | cut -f 2 -d ":"`
dd if=/dev/zero of=vol_$ENC1\_$PLATFORM bs=1024 count=2048
# special case syntax for special case "none"
if [ $ENC1 != none ];then
losetup -e $ENC2 /dev/loop0 vol_$ENC1\_$PLATFORM
else
losetup /dev/loop0 vol_$ENC1\_$PLATFORM
fi
mkfs -t msdos /dev/loop0
mount /dev/loop0 /mnt/
echo $ENC1 > /mnt/$ENC1.txt
umount /dev/loop0
losetup -d /dev/loop0
echo
done

echo -- can you read it back? -------------
for ENCTYPE in $LIST ;do
ENC1=`echo $ENCTYPE | cut -f 1 -d ":"`
ENC2=`echo $ENCTYPE | cut -f 2 -d ":"`
if [ $ENC1 != none ];then
losetup -e $ENC2 /dev/loop0 vol_$ENC1\_$PLATFORM
else
losetup /dev/loop0 vol_$ENC1\_$PLATFORM
fi
mount /dev/loop0 /mnt/
ls /mnt/
umount /dev/loop0
losetup -d /dev/loop0
echo
done