If anyone that has problems with it running, I assume it crashes at startup with a crash report? If you could copy/paste the entire information into an email and send it to me (dan at kulp dot com), that would be great.
Also, if you could run:
otool -L /Applications/xLights.app/Contents/MacOS/xLights
and send that output as well as:
otool -L /Applications/xLights.app/Contents/Frameworks/*-3.0.0.3.0.dylib