Are you using the exact same hardware (sound card) and plugin settings on both systems?
Please note that quality and oversampling settings are not saved in the preset.
I have tested your preset on my hackintosh dual-boot system,
My test was done using a phase cancellation test feeding the X50 with a 10 seconds clip of pink noise.
The difference between OS X and Windows version are -132 dB difference on default settings and -80 dB using your preset (with TSE808 enabled).
In other words, I can't recreate results similar to yours!
As a side note, the original post was made for v2.0.1 when I used a different FFT routine for Mac and Windows versions but v2.4.5 and up uses exactly the same audio processing code.
Please provide the exact settings used, audio card sample rate and buffer size on each system,
rendering settings in Reaper etc