Thanks Jenny and Trail_Mystic. Yes I have reinstalled SetPoint latest version but when I start it, it only shows the keyboard and tools tabs, no mouse tab and I get a popup message 'Logitech does not support all of the Logitech devices connected to your system. Please use Logitech Options app. The Options app left/right assignments doesn't have anything specific for games. Really frustrating because my old mouse and the new one are the same model. I've started some of my older games like Myst V, Riven, Safecracker etc and they are all playing left handed ok with just the Windows mouse setting. I have waited so long for Myst IV to be updated and was so excited when it became available on GOG, isn't that always the way? I find it too hard trying to play right handed. I might try the Gaming Software and see what happens.
"What do you hear Starbuck?". "Nothing but the rain Sir". BSG