Glassboy, thanks for the help. But today my problem has magically disappeared without having changed any settings..... Diagrams are now shown in the reports as before. Completely weird behavior, probably due to Windows...

. The issue had nothing to do with the documentation template I used and neither with the particular model since it occurred also when I created a new model and used a standard template. It happened also with small diagrams that easily fit on one page; they were cut off at the right and lower side to a size of less than 10x10 cm.
But everything is back to normal now. So the advice to anyone experiencing the same problem is: do nothing and try again tomorrow....

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