I’ve used Mac and Win for years with few issues. The one known issue is that profiles (ICC/DCP/LUT) are written to dop as absolute paths, that are inherently not portable, and in that case you either get an error message when opening an image on the “other” platform or the profile is silently ignored. (Can’t remember if the error is on Mac or Win offhand.) As long as I’ve avoided profiles, things have mostly just worked, and when I have run into incompatibilities DxO has fixed the problems after I’ve reported them.
That said, DxO has recently made a mess of this, as I wrote here.
Could it be that you’re using DCP or LUT in your editing?