That's what I was up to: However, the card is not recognized as a slave drive when I scan for it using HDinsttools, it only shows my current drive. I only see one drive in the window.
Is this a new card or an old one that had a previous Workbench install?
I've had some CF cards that wouldn't show up on my A4000 via my FastATA, however the Buddha on my A2000 would recognise them and once prepped they worked fine on the A4000. Others had no problem on the A4000.
What happens if you make the CF card reader "Master" and the Hard drive "Slave"? IIRC correctly I had issues until I configured one of my IDE connectors this way, although I now need to have a CF Card inserted in the reader at all times otherwise it doesn't detect the slave Hard Drive.