Startup Disk Creator will not load certain ISOs

[Alan]

Startup Disk Creator in Ubuntu 12.10 will not load ISOs that would load under 12.04 and earlier.

In other words:
* run Startup Disk Creator
* click "Other" button
* select an ISO and click "Open" button
* ISO does not appear in "CD-Drive/Image" list

This is true for ISOs that have not been changed since last use and have been used successfully to create USB boot disks in prior versions of Ubuntu. e.g.
- clonezilla-live-20120127-oneiric.iso

And for other ISOs that are live CDs, e.g.
- dban-2.2.6_i586.iso
- Fedora-17-x86_64-Live-Desktop.iso

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: usb-creator-gtk 0.2.40ubuntu1
ProcVersionSignature: Ubuntu 3.5.0-18.29-generic 3.5.7
Uname: Linux 3.5.0-18-generic x86_64
ApportVersion: 2.6.1-0ubuntu6
Architecture: amd64
Date: Mon Nov 19 08:03:33 2012
EcryptfsInUse: Yes
ExecutablePath: /usr/bin/usb-creator-gtk
InstallationDate: Installed on 2012-11-12 (7 days ago)
InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120823.1)
InterpreterPath: /usr/bin/python2.7
MarkForUpload: True
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: usb-creator
UpgradeStatus: Upgraded to quantal on 2012-11-17 (1 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.