In history, a user can view pages, version after version, to find a change.
He can do it using the left and right arrows when viewing a page.
In the top nav bar (t_navbar) the buttons doesn't refers to the actual page he is previewing (displayed) but to the actual version of the page published.
Gary may be consulted for better wording. ;-)
To help developers solve the bug, we kindly request that you demonstrate your bug on a show2.tiki.org instance. To start, simply select a version and click on "Create show2.tiki.org instance". Once the instance is ready (in a minute or two), as indicated in the status window below, you can then access that instance, login (the initial admin username/password is "admin") and configure the Tiki to demonstrate your bug. Priority will be given to bugs that have been demonstrated on show2.tiki.org.