As far as I know Parallels (so as Vmware Fusion) are Windows virtual machines that require the installation of the Windows OS. Crossover (and Darwine) are Windows library emulators that allow to run Windows applications without the need to install Windows, and I guess lower degree of compatibility.
That's correct, nothing to add.
BTW francois, I have seen Histogrammar running on Crossover without any problem, maybe you have to do some config adjustment.
BR
Thanks for the info, I'll try with different settings. I just tried with default settings and it's very likely that I missed something.
