This is actually not a conflict or issue between BPS Pro and WP PDF Stamper and is just a procedural step required by the WP PDF Stamper plugin. If you are creating your custom php.ini file in BPS Pro you will need to add the ioncube extension in your custom php.ini file: Example: zend_extension=/usr/xxx/php/modules/ioncube_loader_lin.so (this is just an example of the ioncube extension – you will need to get the specific extension from your host’s help pages).
Example Error message: Site error: the file /xxxxx/public_html/wp-content/plugins/wp-pdf-stamper/wp_pdf_stamp1.php requires the ionCube PHP Loader ioncube_loader_lin_5.2.so to be installed by the site administrator.