1.

I'd like to have a KPart loaded when audiocd:/ is requested. I can't
do this based on mimetype because audiocd:/ has a type of 'directory'.

Is there a way to load a part based on URL ?

The other tricky part is that the part must not be loaded if a filename
is specified, e.g. audiocd:/track01.wav

2.

KIO's filter mechanism seems to be designed specifically for
decompression of specific mimetypes.

I'd like to compress data, but the codec is selected by the
user and obviously I don't want it to be used every time they
try to open a WAV file.

Any ideas ?

Rik