I installed a trail version of Helix Native 1.91 about 10 days ago and it worked up to now, but since today the plugin does not open and Logic gets stuck - so I have to Force Quite the application.
In a thread it was suggested to delete the installation files and reinstall - it did it several times without success.
The internet connection is fine, as I also downloaded the installation file and checked the MD5 hash.
I also tried with another DAW (tracktion), but same behaviour.
What I deleted before reinstallation:
/Library/Application Support/Avid/Audio/Plug-Ins/Line 6
/Library/Audio/Plug-Ins/VST/Line 6 (did not exist)
/Library/Application Support/Line 6/*