This should work now for the current version. I didn't get any feeback when I first made it, I went through and fixed it for the current beta firmware. I think it will work with the current official firmware but I'm not going to revert to confirm.
It definitely won't work with the launch firmware, or any firmware that doesn't have the Audio Compatibility bit option.
I'll also add that since Boost went away between XIM4 and Apex, not to mention in XIM4 it was used for other things in experimental builds, any config that used Boost in the original intended fashion isn't going to work right. I'm considering making/integrating a tool that would apply the old boost value directly onto the curve (i.e. moving all the points in the curve up by the boost value multiplied by whatever the correct conversion factor will be) but I don't know if there is demand for such a feature or this conversion tool in general.