I thought I'd solved this problem...well, it seemed to work...temporarily...until now!
I'd copy the document to another site and work on it there. Then once it was alright, I'd paste it here. That seemed to fix the whole paragraph space issue...i.e. if there was no paragraph space where I was working on the document at another site, no amount of paragraph spacing here (generally) would introduce a paragraph break.
That sucks...as in if I introduce a paragraph space at THIS site, it SHOULD stay there! It doesn't.
And now, for some reason, after this solution - of sorts - it now doesn't seem to be working...the same issue of paragraph spaces is starting again. Perhaps this has to do with me editing the document at the other site and trying to introduce those changes here.
All very annoying. Just wasting my time with nonsense.
I'm guessing the 'solution' is to make all the modifications I want to the document in one go at the other site and then introduce that document to here. The thing is, it takes me some goes to get the document right.