lets try a last shot, if you can get access to the readers drive again.
I did a quick file compare of Rootfs for 300/505 -and kartu
is right, they are almost identical. Beside of 4 files (*.lnk doesn't count)
- lib\modules\2.4.17_n12\kernel\drivers\usb\g_file_s torage.o
- lib\modules\2.4.17_n12\kernel\drivers\usb\s1r72v17 _udc.o
Though filesystem related, they shouldn't be the problem.
Please (re)download the PRS+2.0.18
installer for PRS-300 and extract it into a folder.
Download attached file "installer greenclaws.txt" rename it to "installer.js" and replace the one in "PRSPInstaller/Sony Reader/software
Copy the folder /PRSPInstaller/ to the IM of your reader, disconnect USB.
PRS+ Installer Menu should pop up.
Modifications in the script are commented with "greenclaws"
Script should now accept 505th fw-version string.
The function initTools will copy /opt0 and /opt1 into a folder /greenclaws in IM.
initTools is called before reboot or backup and of course flashFSK.
I would suggest to try the option "7" "backup"
Then reconnect USB and try to retrieve the backup and log files from IM.
Put the folder greenclaws - containing /opt0 and /opt1 into a archive. Put it onto a filesharing server like http://www.file-upload.net/
and PM the link to kartu
Disclaimer: modification to installer.js are not tested so I can not guarantee that the script will work as intended.