As for the inverted list, the first page will have the newest post as the very first post and the original post as the very last.
As for where the original post appears, that's more of a layout coding issue. I'm sure it's been done on SMF boards before, but a lot of that code is original home brewed code.
however in the meantime, there is always the option of clicking the "NEW" icon next to a thread that has received a post you haven't viewed yet. That will send you directly to the very latest reply in that thread. also there is the "Show unread posts since last visit" link at the very top left of every page (under the EX500 logo in red). there is also the option to subscribe to every new thread that gets created so that it shows up in your email's inbox.
just some ideas.