I spoke too soon - I assume it shouldn't take over 5 minutes for fsleyes to load. It's put up the startup screen, and is still loading. the terminal has the following: - GLContext callback function raised NullFunctionError: Attempt to call an undefined function glutInit, check for bool(glutInit) before calling Traceback (most recent call last): File "fsleyes/gl/__init__.py", line 593, in create File "fsleyes/main.py", line 384, in realCallback File "fsleyes/gl/__init__.py", line 381, in bootstrap File "site-packages/OpenGL/GLUT/special.py", line 333, in glutInit File "site-packages/OpenGL/platform/baseplatform.py", line 407, in __call__ OpenGL.error.NullFunctionError: Attempt to call an undefined function glutInit, check for bool(glutInit) before calling Yours Helen Beaumont PhD ISBE University of Manchester Stopford Building, Oxford Rd Manchester M13 9PL Tel: 0161 275 1254