Good luck with Sony responding to this. There has been general griping about the Explorer and lack of discrete codes with the changers for a while. This interfaces for these changers is a disgrace. There - vented again.
Have you looked at Leo Nudel's SuperNudelist to manage the player? Then you can set up your "Enter, Enter..." macros as "before" and "after" buttons (you'll have to do a bit of reading to figure out SNL but it is really worth it.
[Link: ox.compsoc.net]I included a 20 sec delay in my "after" button macro to let the player wind up, select, then send the enter command to clear the screen. You need to be careful to keep the remote pointed at the screen for the 20+ seconds though, or it will miss the final enter command.