Thank you for the details, it made my work much faster.
I have implemented a small snippet into one of the plugin files to filter results by author. To give you more control I have created a file in the plugin directory called form_ids.txt, where you can enter the search form IDs you want to apply this rule. (wp-content/plugins/ajax-search-pro/form_ids.txt)
Add the form IDs into the file separated by a comma as you can see there.
I'm going to add an option to the upcoming release to show posts where the current user is the author, so you don't have to worry about losing it when updates. You will only need to enable that option for each instance after updating.Best,
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