Hi,
Could be it still should work, but it is not supported. That is an answer.
For the moment that IS the answer.
So far, nobody here at the forum has claimed that it worked well.
Just seen a few problems reported with both Fusion 6 and Fusion 7.
While Fusion 6 might have worked well for you with El Capitan, it had some issues.
I seem to recollect, something with Windows 10 support and something with unity, but.. if you don't depend on that, then it "works fine".
But I might remember the exact issues wrong at the moment.
So sure, do try. We'd love to hear your findings. :smileyhappy:
(Not that I personally depend on older versions of Fusion, but it is always good to know the outcome as more people will ask the same question over time)
Fusion 8.5 and Sierra is indeed supported.
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Wil