After downloading, installing, repairing, removing, restarting computer multiple times I have reverted to V5.0.5 which does work. O.S. is W7 HP running on Lenovo T420. I thought the the file was corrupt but have tried downloading from more than one location and multiple times.
“Graphical mess” might point to a possible variant of the OpenGL blacklist issue. If you want to give V 5.1.0 another try, turn off the option ‘Use OpenGL for all rendering’ in ‘LibreOffice’ > ‘View’. Your graphics system / drivers might be not compatible with OpenGL. Versions to come should have be fixed the bug in this case.
Thank you for your response. I note that V5.0.5 has the OpenGL option turned off. I will reinstall V5.1 again, turning off the “Use OpenGL” option and report back.
If OpenGL rendering already was turned off in your user profile for V 5.0.y, the setting should also be obeyed by a V5.1.y installation replacing the older one. I thus not am optimistic about your succes. On the other hand I cannot think of another plasuible reason for your issue.
You may use a PortableApp packaged version on 5.1 for further testing. This will not afflict your installed 5.0, but also show possible hardware/driver issues.