Did you then install the new configuration files and update them with your actual configuration? You probably have some old config files sitting there that are not compatible with your new version.
The best way would be to delete any .php files found in the /settings/... and then check whether the setup wizard is enabled or not
See http://ez.no/developer/ez_publish_3/documentation/ez_publish_3/howtos/enable_disable_the_setup_wizard
As I said, the PHP memory on my install caused blank pages. If it is at 8 or 10MB try setting it to 20MB or something like that.
