Outliner
The Outliner 2.0 is a fast and easy to use scene management tool. It has a wide range of features, including selecting, hiding, freezing, linking and grouping objects in the "Hierarchy Mode". In the "Layer Mode" you can organize your scene by dragging&dropping objects from one layer to the other. What's more, the Outliner offers support for nested layers, to manage scenes more efficiently. The interface is nimble enough to keep it open constantly.
Compared to the previous version (1.6.1), there are many improvements. Most notable among them are: hugely increased performance, improved stability, nested layer support and many small tweaks to improve the ease of use. For a list of all changes, click here

Comments
You got altenate material
You got altenate material button(with matte/shadow material for example) which you can switch on/off,in off state objects have their usual materials and in on state all objects on layer are asigned with alternate material.Usefull for setting up render passes.peace
Could you explain this a bit
Could you explain this a bit further? I am not too familiar with the Onion, so I'm not sure what you mean here exactly.
Is it posible to implement
Is it posible to implement alternate propreties/material switch on per layer basis(ala Onion)?
Something I just realised
Something I just realised about your second problem (selection backgrounds): it would seem like you have visual styles disabled in windows, correct? I just noticed the rather odd looking plus/minus buttons. It looks like they were expected to be a pixels or two larger (oddly drawn + and - itself, done by 'me', are out of place too). Perhaps that's causing the displaced selection backgrounds too..
I've fixed the two issues
I've fixed the two issues with docking in max2012/win7.
http://code.google.com/p/outliner/issues/detail?id=1&can=1
http://code.google.com/p/outliner/issues/detail?id=2&can=1
But it'd be nice if some people could test and verify this. So please contact me through the Outliner website http://script.threesixty.nl/outliner/index.php/contact and I'll send you a test version.
It is tedious indeed. A
It is tedious indeed. A quicker way of doing it would be by running this line of maxscript in the maxscript listener (F11):
cui.floatdialogbar outliner_main
I am looking into the issue now and have been able to reproduce it in 3dsmax 2012 on windows 7. And I have also done a little test where a dialog did seem to be undockable, so there is a little bit of hope :)
PJanssen, I'm using Windows 7
PJanssen, I'm using Windows 7 x64. May be that's where the problem lies. I've read the workaround so I can undock it if I change the ini file but it is a bit tedious since I have to restart the application. The point is, we should be able to undock it from Max by grabbing a handle that any undockable UI element in Max has (like the Ribbon or the Main toolbar for example).
Another problem I found - the background behind the active element stops abruptly at the right half making the last character almost unreadable. Please look at the screenshots I've attached to see what I mean. In the second image I'm showing my suggestion.
Despite of these minor issues which I'm sure you'll get dealt with I think that the tool has a great potential! I'm already using it in my workflow. :)
vbn, I can't undock from the
vbn,
I can't undock from the interface either. There's a way though. Open outliner_prefs.ini (it's located in AppData\Local\Autodesk\3dsMax\2012 - 64bit\enu\scripts folder) and find the line starting with dockFlag. Change that line to: dockFlag=cui_floatable and save outliner_prefs.ini
You're right about that once it's docked you can't resize it. There's a workaround for this too. Resize outliner window before docking it will keep that setting. Also outliner_prefs.ini keeps window size information, you can change it from there.
Which operating system are
Which operating system are you using? I have tried it on my windows xp installation in 3dsmax 2012 and the undocking seems to work sort of fine. That is, it will undock fine but after a few times it crashes max altogether...
Please see this screenshot
Please see this screenshot showing the problem with the undockable window in Max 2012:
http://imageshack.us/photo/my-images/195/outliner.jpg/