There are no known issues with CentOS7. Sounds like that paticurlar PDF has corrupt or unexpected data that is causing the PDF to fail.
Regarding “the “select the dataset to export” field hangs indefinitely.” issue, create a Formidable View of the table and add the PRO2PDF shortcode to the view, which will give you a list of all entries with a link to their respective PDF.
We are willing to find the issue for you, complete this form if you’d like us to take a look. Be sure to provide the exact form and entry that is exhibiting issues.
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