How to print several plot layouts into one PDF file:
For example there are more plot layouts in one window:
1. File menu - Print queue
2. Here add the different pages to the print queue and select the PDF printing option for each plot layout.
Make sure that all of the PDF files have the same name.
3. If the plot layouts are placed in one window, click on the View option and define all the pages you want to print.
4. This way the files are saved into one PDF file. Here is the result from the 2 page plot layout: