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rumplestiltskin -

I know SFA about KFX, but this might be worth trying:
- save your Windows config folder somewhere safe.
- export your config folder from your Mac to a USB
- import that config folder into your Windows setup
- try the conversion
If conversion on Windows now delivers the same result as you get on your Mac, then your problem is the difference in conversion settings. Otherwise I refer to jhowell's suggestions.
BR