I think later drivers can use two modes, controlled by the setting of the "Handshake Reads and Writes" option (see PDF user manual page 36). The Trumpcard Professional does handshaking in hardware.
Amiga87, can you try with Kickstart 1.3? Reading old magazine articles on the
historical archive page, see Amazing_Computing_Vol_07_11_1992_Nov_page92.jpg
That's a letter from IVS which suggests the old boot ROM could have some problem with Kickstart 2.x.