I have the Pioneer Avic-d1 (Yes I know completely different nav unit but...) I was able to make a dvd rom that had the opening screen and i changed it but used the same file name. On the pioneer the file is BGOPEN2.JPG
The pioneer unit loads its graphic off the dvd and stores it in memory so after, i loaded it the first time i went back to the factory nav dvd. If this is the same way the eclips works just drop the dvd in your computer and explore the files and see what the opening screen is called.
None of this probably helps but you never know.. and it gives me a chance to show off my custom nav screen
