I’ve the following problem when exporting my score as PDF (I’ve created a small example included here).
In my very first page I’ve added the following PNG image (having a transparent background) covering the full page:
To create space for title, author etc. I’ve over imposed some pure white images to cover parts of the background:
Now, the Engrave view shows my page correctly, and so the Print view. Printing directly from the Print view produces the correct page as well.
Instead, if I export the score as a PDF, in the Apple Preview app it appears correct, but when I print it is totally different:
I’ve just installed Acrobat Reader DC, and printing from it produces a right page. So the problem appears only when printing from Apple Preview.