Could you send me the log.txt file, it should be located in your ~/Library/Application Support/.ubercube/data/macos, I don't have a mac so I couldn't test the build. Send it directlyat this link -> https://github.com/ubercube/ubercube/issues/new Thanks for the help !
Viewing post in Ubercube Pre-Alpha 1.1 released ! comments
Issue reported -> https://github.com/ubercube/ubercube/issues/7 Probably not an error in the LWJGL 3 library. I have been wrong before. Pleased to be able to help !!