I know you might have moved on since posting this query, but if you're still interested, there are a couple of small differences. The first one that springs to mind is the options available when you're exporting your final animation - there are slight differences in the available formats. Click the Show More link below the
Key Feature Comparison table and carefully read through the feature. A small number flag up either "Mac only" or "PC only". However, the great majority of features and functionality are cross-platform.
The other difference that springs to mind has upset a few people recently - the new hand/body mocap features that become available as options with CA4.2 are currently only available to Windows users. This is because the mocap developers - not Reallusion - only provide up-to-date support to developers working on the Windows platform.
Hope this helps!
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Cartoon Animator 4 Pipeline (always the current production version, unless otherwise stated)
Mac mini M1, macOS Big Sur (11.6.5)
Signature data last updated 2022-05-15