Hi Ernest,
I am trying to debug this following your hints (thanks!).
So, I rebuilt the result page in a simpler way.
I also found that, by deactivating “Replace the default theme search with:”, the standard search works, as well as filters. However, as soon as I override it with Ajax Search Pro, the filter is gone.
Redirection to result page overridden by Ajax Search Pro is triggered by both magnifier and return button.
Please have a look at the screenshots attached and let me know your thoughts.
Best,
Samuele