Macromedia Director is highly extensible. Extensions in Director are called Xtras and can add support for new media types, new coding structures and routines or authoring helper tools. I've built several authoring/debugging tools for Director over the years. To install these xtras, just save the dcr files into your "/Director/Xtras/" folder.

ZapFPS IconZapFPS - Director Tool Xtra
When building graphically intense games in Director, it is often useful to track your frames per second (FPS) during playback. This xtra shows a running graphical representation of how fast or slow your Director movie is playing back. This is actually the third iteration of the xtra and it tracks current and average playback speed. One note: this xtra works best when playback frame rate is set to 999 FPS (maximum frame rate in Director).
>> Download the xtra

NetWatcher IconNetWatcher - Director Tool Xtra
While trying to debug a complex Net application built in Director, it is useful to have a Net process trace tool. That's the function of the NetWatcher xtra. It will show progress of all Net operations executed by Director and will optionally trace data about those operations into the Message Window.
>> Download the xtra

WindowTyper IconWindowTyper - Director Tool Xtra
Director has the ability to spawn new windows in an application. These windows are self-contained and can, not surprisingly, be displayed using the standard window types available in the containing Operating System. These are called Movies in a Window (aka MIAW). MIAW window types are accessed by setting the windowType property of the window (i.e. window("some_window").windowType = 4). Rather than try to remember all the windowtypes, I created this xtra which allows me to look through all the available options quickly. Note that many of the windowtypes look similar. A few to remember are windowtypes 1, 2, 4, 5 and 49.
>> Download the xtra

ZapDebugger IconZapDebugger - Director Tool Xtra
Building applications in Director sometimes requires live debugging inside of the application. This tool was created to make this process easier. It shows memory usage, provides a generic method for executing arbitrary code and has simplified variable watcher. I've found it useful more times than I can count.
>> Download the xtra

ZapColorizer IconZapColorizer - Director Tool Xtra
Built during the Director 8 beta, this xtra will alter a graphic member's RGB, brightness and contrast. It's not the most useful xtra and could certainly be made more efficient, but it is an interesting experiment.
>> Download the xtra