Thanks, K1n9_Duk3. That was very helpful indeed!
Also, I happened to notice that actors.txt gives the decimal values for all of the objects, but the DN2 editor has hexadecimal values.
So while the text file helps, there's still a bit of work converting those numbers. (Does anyone know a fast way to read decimal value as hex without using a converter?)
I'm thinking that in the next release of your editor, you should either A) Have a graphical object selection menu, or B) At least a special hot-key menu that gives you the same information as actors.txt, but prompts you for a selection. This seems like it would be easy to implement, but may or may not conflict with your condensed and efficient GUI.
This is fantastic. K1n9_Duk3, you are my hero.
PS. The drag-n-drop method works for extracting graphics from .MNI files, but not for importing back into the game. The documentation provided with the editor contains no information on the correct command-line parameters, so I'm a little bit lost here.