[Plugin: NextGEN Gallery] Error after upgrading gallery

Hi – I have a problem with several installs of nextgen – after installing the new version it requested a database update which i did – then when i click on the nextgen tab- it goes to a page in the site saysing – Sorry – the page deoent exist.
I can access some of the gallery settings if i choose the drop down, but the main overview for example – gives the same error.

Id there a work around for this please?

http://wordpress.org/extend/plugins/nextgen-gallery/