Hello Peter,
Thanks to hear that you have found a solution. I am sorry for not being able to get back to you sooner.
For disallowing crawling by the Search Engine. You can Mask Download Link, If you mask the download link, bots will not be able the find any public download link easily. You are able to find this setting from Downloads > Settings> Basic Settings. please check.
And another way for making disallow Crawling Download Manager Pages on Google, Bing + search engines is, Add the following code at the end of your active theme’s functions.php:
function noindex_for_wpdm()
{
if ( is_singular( 'wpdmpro' ) ) {
echo '<meta name="robots" content="noindex, nofollow">';
}
}
I hope it may help you. Please check and let me know for further assistance.
Thank you and regards