Today we have released further updates to KB and Tags extensions.
I dont have a full changelog, but a lot of bug fixes, including SEF plugin issues and other minor tweaks have been included.
Compatibility with KB and sh404sef/SEF Advance 2008 should also be fixed now.
And the other main issue was Tags and Layouts, these all now work correctly 
Note: The main bulk of this release is to push out a new xajax plugin version. If, after upgrading FROM A WORKING VERSION to the latest version of either of these extensions you get a blank page then just delete /plugins/system/xajax.* and refresh the page – that will force a reinstall of the new xajax plugin – this is required on all sites!