Pšenda: "After all, it goes without saying that each user, before buying a product, finds out and tests whether it meets exactly his expectations."
Yes, I did try the program, but not with the full 400 pages. I was also swayed (foolishly?) by the lavish and flashy website portrayal of what was a publishing program. And the price, of course, was right. To see that it 'met exactly my expectations' would have meant me formatting the entire thing in the trial version, but, being impressed at that point, I bought the full version. That was a mistake, apparently!
I wrote the novel in an old version of MS Word, and had no problems with file size, so why can't Affinity Publisher match the formatting ease-of-use of the 2003 version of Word (or am I missing something obvious here)? Of course Publisher offers much more scope for fine tuning of formatting, which is why I bought it, but if it's that extended scope that causes the problems then all I can say is -- "needs more work".