Try swapping CF cards to make sure problem is with the enclosure and not with one of the cards.
Sometimes a connector with 80 pin PATA is really just 40 pins, extra ground pins are not really connected to ground anyway. Sometims the enclosure only works with 80 pin PATA, but this is rare. Such devices will never work on 40 pin PATA. Check with the seller.
Also, can be issue with OS, what version of Workbench and Kickstart? If 3.1 Workbench, never upgraded, then could just be using 8GB card or 4 GB boot partition.
Finally, what software device are you using on PowerFlyer/FastATA? Is it recent or from 10 years ago? That is worth checking, might need updating.
