Nested XAR files

I've already requested something similar in another post here, but I've recently started using another software that solves this problem so elegantly that I believe that this is the optimum way to do so.

Often, you will want the same element (graphic, text block, group etc.) in multiple places and still maintain the possibility of editing it in a central place, with all copies updating accordingly ("true clones", "Movie clips" in Flash etc.).

I've recently switched my video editor to Sony Vegas Pro, and there, you can simply drop an entire Vegas project file (akin to Xtreme's XAR file) on the timeline inside another project file. You can even drop an already-nested project file again in another project file, and so on. A right-click on such a project file brings up a popup menu "Edit in Vegas", and Vegas simply opens another instance of the application that will edit that project. Saving will signal all other instances of Vegas, and they will update their timeline with the newly saved project.

This is so elegant and flexible, I can't imagine a better way for Xtreme:

When dropping a XAR file into another XAR file (already possible), add a modifier so that it will not COPY the contents, but create a REFERENCE to that XAR file that can be treated like a regular object (scaling, rotating, live effects etc.), but that cannot be edited directly - instead, double-clicking it will open another Xara instance which will open the referenced XAR, and saving from there will update it in the other Xara instance.

Perfect!