Open file from win rhino 6 on mac

Is there any way to important or open rhino6 file from PC on Mac running rhino5?

We used to be able to open files from newer rhino versions by importing them into older installations…why can’t we any more?

An older version of Rhino can never open a file from a newer version.
In Rhino 6, use SaveAs/Export to make a V5 file, then Rhino V5 can open it.

If you have Mac V5, then you can also download and install the Mac V6 WIP.
Then you can do the conversion yourself.