For the love of play-on words, and perhaps the need for a good way of mapping the OOK universe, I have created and nearly finished Universal Layout. It's fairly simple...
Shift+click to add systems or objects
Ctrl+click to remove them
Option(Alt)+click to edit a system's layout
Cmd+click to move an object.
Right-clicking an object will let you edit the object's details. For systems this is only the name, but for objects within a system there are other options.
The few features I have left to add include copying objects, icon-detection (based on supplied object type) and a combo box(drop-down menu) for the object type selection. Additionally, I have a few graphical bugs to fix. At this point the editor is around 95% done and I am proud to present it here. Sit back, enjoy, and let me know what you think.
Coming up in the near future - In-game map generation from the completed Universal Layout app.
Looks mad! Looking forward to updates! :D