interface becomes unresponsive if setting preferences

[Heling Yao]

While testdrive-gtk is running, clicking and setting the Preferences would make the program unresponsive. need to kill the program and restart.

Or the Preferences menu item could be grayed out if it's a known issue.

Thanks

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: testdrive-gtk 3.24-0ubuntu1
ProcVersionSignature: Ubuntu 3.11.0-15.23-generic 3.11.10
Uname: Linux 3.11.0-15-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.12.5-0ubuntu2.2
Architecture: amd64
Date: Thu Jan 23 04:56:05 2014
InstallationDate: Installed on 2014-01-20 (2 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: testdrive
UpgradeStatus: No upgrade log present (probably fresh install)