Reverse chron order for posts on a per-user basis is something that Invision just doesn't support out of the box.
You can, however, click the date in the latest reply column of the topic which will take you to the last post.
There's also topic previews. When you mouseover any topic on the forum, there's a little black circle with a down arrow that appears in it. Here's what happens when you click it:
As you can see, it shows a couple of things: a preview of the first post, a preview of the first unread post, and a preview of the last post. You can click on those "first, first unread, last" links to take you directly to those posts.
Try it out.