External Preferences Dialog - Can not choose configuration

I have problems to choose configurations in the external preferences
dialog box in SW-2003 SP-5. The area is grayed out. See
http://www.audiovehicle.com/lasse/untitled.jpg

I have a main assembly with two different configurations of one
sub-assembly.
Those two sub-assembly configurations contains different configuration
of a base part and two different configurations of one in-context
part..

The two configurations of the in-context part does not updates
correctly in the assemblies. So I have need to link the in-context part
to right assembly configuration. BUT IT IS GRAYED OUT ???

It doesn't matter if I RMB on the sketch or feature or anywhere in
the part or in the assemblies. I have tried everything. I have open up
both assemblies. I have changed external preferences options to
different settings but NOTHING "opens" configuration field in
external preferences dialog.

 

Now should the link to the picture work

 

Zacca

I could be wrong but I think you have to have a feature or other item(s)
in the list selected for the grayed out areas to become active

Ben