Sorry for the lateness of my reply but it was the chaos before the maelstorm that absorbed my time.
I do appreciate the help from the replies and also from the help & advice received from Ryan Webber via a support ticket.
We are in a good place with the project. One of the things or tricks was to disable the standard intel graphics card that is part of the PC and to run all off the Radeon RX 480 card that is installed on the PC. This is what cleared the Open GL error issue. There seemed little option to bypass or to update the GL drivers in any fashion.
I had updated the win 10 OS to the latest version (H020) and also updated every other driver I could see as part of the troubleshooting. Albeit Isadora was assigned to the AMD Radeon Graphics card, the error persisted until the standard intel graphics card was disabled in the windows device manager section.
We are now just running off the Radeon graphics card for all AV elements.
I have 4no. Epson UST projectors, a primary monitor for control and an integrated windows touch screen monitor that will be an audience interactive device as part of the presentation. As you can see, I have 6no. monitors whereas I have 5no. outputs on my AMD Radeon card. I am loathe to re-enable the normal graphics card as this is what caused the Open GL error and for the moment, things are working fine.... I have some Matrox triple heads to go so that will probably be the answer for my 5 outputs for 6no. screens.
With the latest version of AMD software and Windows 10, the selection and assigning of a program to the AMD card is now contained in the Windows Displays properties and not in the AMD software. I had asked this question over on their forum as all the guides I encoutnered said look for the option of switchable graphics in the settings menu to no avail....
Again, thank you to one and all. All advice and guidance is and has been much appreciated.