I own 3 of the DVP-CX985V changers, but have never seen the Disc Explorer interface unfortunately. I wish I could be of some help in that regard. Sorry.
If you find you need another solution for accessing your DVD's in the changers there are alternative solutions out there. I use my TSU7000 for que'ing up the DVD's in my changers.
You could easily retrofit my .pcf file for use with your changer since it uses the same IR codes. I've had several people email me who have gotten their changers and DVD collections up and running in just a day or two using my .pcf file as a starting point.
Check out this
thread for more information if you are interested. Good luck with the Disc Explorer feature by the way. I had read so many negative things about it before purchasing my changers that I already had my TSU7000 waiting in the wings.
-Lowpro