Thanks a lot for this!
I'm not sure if this is an error or intentional since ILBM has no notion of transparency (I think), but I noticed that color 0 appears differently depending on where QuickLook acts. In the file info window it looks fine, in Finder it appears in the correct color but with high transparency, and on the desktop and otherwise as an icon it appears in full white.
@Photon: I would also recommend FS-UAE. It takes a little while to configure, but there is a GUI launcher and the emulation core is up to date with WinUAE.