I found a German tutorial describing the usage of Unity and its major problems with certain applications and certain users as well and patiently I spent a couple of days with the new concept.
1) Neither LibO nor AOO are perfectly integrated applications. They don't merge their application menu into the system wide task bar and contrary to the "integrated" applications they show their usual scroll bars all the time. No problem so far. I can live with that since there is no loss of functionality. These features may be be more important with very small screens.
2) I can make the icon of a running AOO stick to the starter bar but after closing AOO the new starter fails to re-launch AOO.
3) I can not install the desktop integration package for AOO because it conflicts with the one of LibO. Under any other shell this conflict does not impose any problem because you are free to add your own application starters, symlinks and menu entries wherever you want. For regular desktop starters under Unity one would drag the starter from the dash onto the desktop. However AOO does not appear in the dash even when I point to its executable, so I can not add any desktop icon this way.
4) On file system level I can add a symlink to the desktop folder pointing to the AOO soffice executable but that does not launch AOO neither.
So far I can start AOO as second office suite under Unity from a command line only. Personally, I have no problem with starting applications from the command line but many other users will not accept this and stick with one "integrated" office suite only.
OK, let's try harder to get some kind of launcher for a secondary office suite:
Find LibreOffice in the dash and drag it onto the desktop so you can redirect the new desktop link to AOO. Result: Unity creates broken links for LibO or any of its components. Surely a Unity bug.
Let's do the same with some other application, say "System Monitor". Result: I get a working desktop link to launch the system monitor. I can modify the label, change the icon and replace the start command with /opt/openoffice.org3/program/soffice
Success

Being tough enough for Base is the best qualification for customizing the Unity shell
