An update to this. My bad - turns out Kentucky Downs is still KD, not KDF.
I don't know what KDF is, sorry. There's really no need at add KDF to your internal track list.
Some people who do unlimited downloading report getting stuck when trying to download KDF (e.g. for today, Saturday Sept 10). The Data Centre (RDSS1 and RDSS2) reports an error message which (in part) looks something like this, but if you simply scroll the Progress window up to see the earlier part of the message, it really says is had some problem fetching the file:
kdf20110910rdss.zip
In this case, simply remove deselect KDF from the All Tracks List. Then rerun your downloads.
If someone figures out what KDF is, please let me know!
Ted