Characters movements show garbled praphics

Under Unity, on Ubuntu Trusty amd-64, animations and movements of many AMOR characters show garbled graphics.

*This issue was not present on Ubuntu Precise; don't know if it was present on 12.10, 13.04 or 13.10.

System info:

Linux 3.13.0-24-generic #46-Ubuntu SMP Thu Apr 10 19:11:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

Package info:
 *
Package: amor
Status: install ok installed
Priority: optional
Section: games
Installed-Size: 594
Maintainer: Kubuntu Developers <email address hidden>
Architecture: amd64
Version: 4:4.13.0-0ubuntu1
Depends: kde-runtime, libc6 (>= 2.14), libkdecore5 (>= 4:4.13.0), libkdeui5 (>= 4:4.13.0), libqt4-dbus (>= 4:4.5.3), libqtcore4 (>= 4:4.7.0~beta1), libqtgui4 (>= 4:4.5.3), libstdc++6 (>= 4.1.1), libx11-6, libxext6
Recommends: kde-window-manager
Suggests: khelpcenter4
Description: desktop companion
 AMOR, or Amusing Misuse Of Resources, displays an animated character who
 wanders about the screen, doing tricks and giving the occasional hint.
 .
 This package is part of the KDE toys module.
Homepage: http://www.kde.org/
*

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: amor 4:4.13.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.14.1-0ubuntu3
Architecture: amd64
CurrentDesktop: Unity
Date: Sun Apr 20 16:49:42 2014
EcryptfsInUse: Yes
InstallationDate: Installed on 2014-04-18 (2 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64+mac (20140417)
SourcePackage: amor
UpgradeStatus: No upgrade log present (probably fresh install)