Bug / Crash .UnityPackage does not successfully import

[Mitch@PG]

Have tried importing via Asset Store, and via the Assets menu; result the same, as in image below.  

Unity v 2018.2.9.f1 64 bit

This is a newly created project, apart from a cube with a material attached.

Build platform is PC / Mac / Linux standalone.

Please advise if any other details are necessary. 

Have attached image as well, in case the inserted / linked image does provide enough detail.

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Update

On our OS X machine, ObiFluid imports into a Unity 2018.3.0b3 project and runs just fine.  So the issue seems to be with / on my development machine.