bbPress checks capability to create topic own way, not as WordPress itself does for any post type:

if ( current_user_can( $post_type_object->cap->create_posts ) ) {

That’s why URE Pro currently does not change bbPress logic to use ‘create_topics’ as expected, even with correspondent option is turned ON at URE’s settings. I will include the fix to the next update.

Thank you for pointing me this. You may use the solution offered above as a temporal workaround until I will publish the version of URE Pro which will support this correctly.