The standard navigation with html links results quite often in many steps to get to the target page. As alternative we are starting to roll out a vertical pop-out menu system, currently up to 4 levels deep. For users with older or otherwise incompatible browsers - see configuration - the standard html links will be kept as well. Additionally we did add a site index page which opens in a separate window or tab (Firefox)
In compatibility tests with the pop-out menu we had these results so far, organized by OS and Service Pack / Version (Linux):
4 -Virt. Box
3 - Virt. Box
We will be adding to this list as time allows. Also we would appreciate user feedback on OS/browser combinations not listed.