Working with scopes - looking for pointers

Hi,

I want to make a plugin that allows the user to set temporary File Colors (via Scopes) on-the-fly without having to go to Settings to define them.

For example: he might want to give some files a color as a means of quickly categorising it for the task he's currently doing.

For starters, this could be a simple Action Group from an EditorTab that allows the user to say "I want this file to be red" - the plugin will make a Scope pointing to that file, and assign a File Color to that Scope of "red".

I'm looking for some pointers to get me started on the proper way to provide the behaviour of defining a new local Scope, given the file the user performed the Action on. I've read through the IntelliJ source code and seen how the Settings window creates Scopes (which seems quite dependant on the Tree Nodes but I'm sure I can work around it), but I failed to find other plugins that do anything remotely similar.

I'm new to writing IntelliJ Plugins, so I'm looking for broad pointers on the approach I should take to solve this. If I know the broad approach, I'm sure I'll figure out the details myself as I go.

Thanks for any advice you can give =)

Will