Erdal, thank you for your answer.
I can see in your example that IncrementalPreview is set to 0 and, as the Zoom is greater than 100%, the page appears centred in the screen instead of showing the top part of it. This is the problem I originally had, as stated in Report preview centred in screen and zoom greater than 100% - English Forum - combit Reporting Forum .
The solution given to me was to set IncrementalPreview to 1, and that effectively solved that problem, as in the preview window would appear the top of the page. But setting IncrementalPreview to 1 made my preview window not modal and it being modal is mandatory for me.
So, the problem I am facing is how to make the preview window modal while setting IncrementalPreview to 1. Probably there is something I’m doing wrong, as I originally developed my project with version 10 and there was no IncrementalPreview then. Otherwise tell me if I should open a support case in order to correct the previewing of the report so it does not appear centred with IncrementalPreview set to zero.
Thanks again for your help.