Am I reading this right? You need an A600 version of Kickstart with the IDE controller code on it, even in an A500 (one of the first lines at the link above).
From the website: "Since the board emulates the internal IDE-interface of Amiga 600 and it doesn't have ROM of its own, you thus need Kickstart ROM with the driver for A600's IDE."
Looks like it!
Just noticed down in the FAQ that this board conflicts with the Indivision in Amiga 500's. Might be important for some of the other users posting about this topic recently. Personally I tried researching the IDE68K a while back, but got confused by all the different versions and just went with a sidecar HD instead, LOL. :p