I recently upgraded my MacOS to High Sierra (10.13.1). I had no idea when I was doing that that I would lose compatibility with Halion Sonic 3 and the sound libraries associated with it. I started work on a musical composition in Logic several years ago, in 2009, when there were no compatibility problems. I had about 7 tracks in the composition that used sounds/patches from Halion Sonic which I accessed through Logic as an AU plug-in. I never finished the composition and recently re-opened it to finish work on it, and all the tracks that were using sounds/patches from Halion Sonic 3 were not being recognized by Logic Pro X. I did some investigating online, and Steinberg’s website states that currently, there is incompatibility between MacOS 10.13 High Sierra and Halion Sonic 3. Is this incompatibility issue ever going to be resolved? If so, and it’s just not officially released yet, is there a way to obtain a copy of the beta version? If there is never going to be an official compatibility fix, is there a “work-around” solution that I could use? The only thing I can think of now is to uninstall High Sierra and go back to an older version of MacOS, such as Yosemite or El Capitan, open up an older version of Logic, pull up the composition, and record the MIDI/software instrument tracks utilizing Halion Sonic 3 as audio tracks, save those audio tracks, and then re-install High Sierra and import those audio tracks into Logic Pro X. Is there any other option?? Thank you!