[andrewcorser]

First of all: thanks to Klojum for (so far!) having sorted out my difficulty with blank screen...
...following the advice, I have enabled Debug logging, but it displaysi nt he the top left of the dialogue, right over the titles...there is presumably a way of having Debug logging without it degrading the gui in this way?

[Klojum]

Add to your advancedsetting.xml file, and restart:

xml:
<advancedsettings>

    <loglevel>1</loglevel>  

</advancedsettings>

[jjd-uk]

See https://kodi.wiki/view/Log_file/Advanced

Click expand on Opton box to see available logging levels, for debug logging without UI overlay you want logging level 1