Hello Pelle, I installed the QT version 4.8.5 in /usr/local/Trolltech/Qt-4.8.5, the standard location for a home build Qt. I don't know where the install package puts it. Then in ilcinstall/examples/slic/head-.py below the line: #----- install geant4 you set: geant4.envcmake["GEANT4_USE_QT"]='ON' # requires qt geant4.envcmake["QT_QMAKE_EXECUTABLE"]='/usr/local/Trolltech/Qt-4.8.5/bin/qmake' Then do a completely new, clean install of slic, and you can use the Qt version of the G4 window by /vis/open OGLI On a Mac, make sure your graphics card is on "discrete" (the Nvidia card) and not on "integrated", otherwise you won't see anything. This worked for me. Best, Maurik ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the HPS-SOFTWARE list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1