[Andreas]

Guess what, I hate File Edits

Hook: showthread_query

PHP Code:

if ($forum['showfirstpost'])
{
    $hook_query_where .= " OR post.postid = $thread[firstpostid]";
} 


This does show the first Post on all Pages. However, if it has attachments they will only be shown on the first Page.
Don't think there is a way to get this working too without a File Edit, but i'll take a further look.