Hello world fails with default configuration

OS : Win7-32b
PsychoPy version : 2020.1.3
Standard Standalone? (y/n) :y
What are you trying to achieve?: Evaluation

What did you try to make it work?: Hello world

What specifically went wrong when you tried that?:

The message was not displayed. This appears to be a pyglet library compatibilty issue, though I have not modified the installation in any way. Selecting a differnt library in Builder Preferences produces the desired result, however the Preferences setting does not persist and reverts to pyglet. So there are potentially two issues here. traceback below:
Thanks,
G

Traceback (most recent call last):
File “C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\backends\pygletbackend.py”, line 170, in init
style=style)
File “C:\Program Files\PsychoPy3\lib\site-packages\pyglet\window\win32_init_.py”, line 134, in init
super(Win32Window, self).init(*args, **kwargs)
File “C:\Program Files\PsychoPy3\lib\site-packages\pyglet\window_init_.py”, line 571, in init
self.create()
File "C:\Program Files\PsychoPy3\lib\site-packages\pyglet\window\win32_init
.py", line 266, in _create
self.context.attach(self.canvas)
File “C:\Program Files\PsychoPy3\lib\site-packages\pyglet\gl\win32.py”, line 212, in attach
raise gl.ContextException(‘Unable to share contexts’)
pyglet.gl.ContextException: Unable to share contexts

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File “C:\Users\Gordon\Documents\PsychoPy\hello_lastrun.py”, line 72, in
units=‘height’)
File “C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\window.py”, line 434, in init
*args, **kwargs)
File “C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\backends_init_.py”, line 32, in getBackend
return Backend(win, *args, **kwargs)
File “C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\backends\pygletbackend.py”, line 177, in init
fullscreen=self._isFullScr,
AttributeError: ‘PygletBackend’ object has no attribute ‘_isFullScr’
Exception ignored in: <bound method Window.del of <psychopy.visual.window.Window object at 0x0A955690>>
Traceback (most recent call last):
File “C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\window.py”, line 577, in del
self.close()
File “C:\Program Files\PsychoPy3\lib\site-packages\psychopy\visual\window.py”, line 2196, in close
self.backend.close() # moved here, dereferencing the window prevents
AttributeError: ‘NoneType’ object has no attribute ‘close’