Hi lyes, it's not really possible to change the scene browser like that just with an external downloaded plug-in script, to alter things like that would require changes more directly to the scene browser mechanisms.

Also there are some difficulties with what you are showing, I'm not sure how certain things would work, I'll try to explain:



Re: Click to add selected to the named group - you're showing a color swatch there for each name. But the problem with implementing that is that there is no restriction for that name to only belong to a single object, it is possible for multiple objects to have that name and each of those objects can be assigned different styles. So there is not necessarily just a single color that is associated with a name, there can be multiple objects and therefore multiple colors associated with a name.

In the future I do want to add a kind of drop-down menu to each item with some additional actions on it, and one of those would be "Assign to this name". Until then the "AssignName" plug-in that was posted earlier in this thread can help out:
http://moi3d.com/forum/index.php?webtag=MOI&msg=3830.4



re: Edit style - you can edit the color of a style currently by holding down Ctrl while clicking on its color swatch. That will open up a color picker so you can set the color.

Also another shortcut for editing a style is if you right-click on the style line in the Properties Panel:



That will pop up the "Edit style" dialog that lets you edit either the name or the color of the style.




re: Add style entry at the bottom of the list - there is already an entry for that on the style tools menu, to access it press this button here to launch the menu:



Then you will see the "Add new style" option on that menu, here:




It's also possible to set up a keyboard shortcut that will bring up the "Add new style" dialog box, to do that see this previous post:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2987.5


- Michael