Firstly, I changed the key assignments in KDE, cleared the bothersome ones as I don’t use them.
The main thing I wanted to custiomise was the font sizes as they are a bit small. I did the following :-
1. Installed MEW 9.10 in an identical location on a neighbouring Windows PC
2. Cleared the config directory on the Windows PC (important because of case differences)
3. Copy contents of directory between the two to make changes to the configuration.
Messy, but it works and fortunately not a frequent requirement.
My screen is now much more readable.
I haven’t looked into how to call a Linux compiler yet.