Dragging icon from dash to launcher on other monitor causes window stacking to get messed up

I have a dual-monitor setup - my laptop screen, and an external display to the left. I have launchers configured on both monitors. I can reliably get compiz to mess up the window stacking order by following these steps:

1) Move mouse to right hand monitor (laptop screen).
2) open dash
3) Drag an application icon off the dash, over on top of the launcher on the left hand monitor.
4) Drop the icon on the launcher.

At this stage, the dash pops up on the left hand monitor (that's a bug in itself), and clicking on the dash sends clicks to the window behind it.

The dash on the right-hand monitor dissapears, and the launcher icons remain saturated after I've released the launcher icon.

From this point, the only thing I can do is restart unity/compiz.

See attached video.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: unity 5.8.0-0ubuntu2
ProcVersionSignature: Ubuntu 3.2.0-21.34-generic 3.2.13
Uname: Linux 3.2.0-21-generic x86_64
NonfreeKernelModules: nvidia
.proc.driver.nvidia.gpus.0: Error: [Errno 21] Is a directory: '/proc/driver/nvidia/gpus/0'
.proc.driver.nvidia.registry: Binary: ""
.tmp.unity.support.test.0:

ApportVersion: 2.0-0ubuntu4
Architecture: amd64
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,place,session,mousepoll,vpswitch,snap,grid,resize,gnomecompat,regex,imgpng,move,animation,workarounds,wall,unitymtgrabhandles,expo,fade,ezoom,scale,unityshell]
CompositorRunning: compiz
Date: Wed Apr 4 16:08:46 2012
DistUpgraded: 2012-01-18 11:08:01,845 DEBUG enabling apt cron job
DistroCodename: precise
DistroVariant: ubuntu
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
MachineType: System76, Inc. Serval Professional
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-21-generic root=UUID=1ad6d244-76e1-48be-b7b7-983c06853cdb ro quiet splash vt.handoff=7
SourcePackage: unity
UpgradeStatus: Upgraded to precise on 2012-01-17 (77 days ago)
dmi.bios.date: 08/09/2011
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 4.6.4
dmi.board.asset.tag: Not Applicable
dmi.board.name: Serval Professional
dmi.board.vendor: System76, Inc.
dmi.board.version: serp7
dmi.chassis.asset.tag: Not Applicable
dmi.chassis.type: 10
dmi.chassis.vendor: System76, Inc.
dmi.chassis.version: serp7
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr4.6.4:bd08/09/2011:svnSystem76,Inc.:pnServalProfessional:pvrserp7:rvnSystem76,Inc.:rnServalProfessional:rvrserp7:cvnSystem76,Inc.:ct10:cvrserp7:
dmi.product.name: Serval Professional
dmi.product.version: serp7
dmi.sys.vendor: System76, Inc.
version.compiz: compiz 1:0.9.7.4-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.32-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 8.0.2-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 8.0.2-0ubuntu3
version.nvidia-graphics-drivers: nvidia-graphics-drivers N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.11.4-0ubuntu8
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.0-0ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20111219.aacbd629-0ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.17.0-1ubuntu4
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20111201+b5534a1-1build2