Xplorer FX + Caetla 0.34 and Memory Card Manager

[AmiDog]

On my setup, Caetla refuses to recognize any memory cards. Interestingly, I can use the mcbackup and mcrestore catflap functions to read and write memory cards, but the Caetla firmware (UI and mclist/mcup/mcdown) refuse to see the saves on any of my memory cards and reports "Card in slot x is not initialized or is uknown format". I've also tried a different PS1, same result.

Perhaps I need to change some setting? Is there any Caetla configuration documentation available somewhere?

edit: The PS1 BIOS does show all my saves and allow me to copy between cards.