That is to say, the 'conversion' is done by the keyboard, not the Data Management Software. This conversion occurs whether the file is loaded from a PC by the Data Management Software or directly from an SD Card.
AC7 Rhythm format is performed by the target keyboard's operating system as the file is loaded into that keyboard's User Rhythm memory.
Z00 files and the newer models will import either the. Because of the vast differences between the older models' sound engines and those of the newer CTK/WK-6XXX/7XXX models, none of the older tone related files will work in the newer models, but because of the similarities in their Rhyrhm engines, the older Rhythm files will work in the newer models. It was the IDES Data Management Software's job to extract the different file types and install them into the target keyboard's appropriate User Memory areas. They were sort of a Casio proprietary 'zip' file. ckf files for the older 76 key WK-3000, 3300, 3500, 3800, etc and their 61 key CTK counterparts were distribution files which could contain a single rhythm, a single tone, a single tone with wave, a single drawbar organ tone, etc or any number or mixture of the same. I do not know if you ever found an answer to this, so. ckf style file and it works pretty well for that, but I don't know how to convert from. Stytockf1.2 will convert any Yamaha style file to a Casio.