The new workflows space report uses Confluence JSON page properties to supply the data to display. These values will normally be updated after each change in the workflow, but on intial upgrade will need to populated.
This will be done as part of a background upgrade task after the 6.8.1x version of the plugin is installed. If you updating from 5.x to a version up to and including 6.8.0 please refer to a separate upgrade notes page.
If for any reason this fails (such as an invalid license) the population long running task can be re-run manually by going the following url as a global admin.
Comala Workflows has started to use active objects tables in the Confluence host database. In this release it is just for read confirmation history data, with more likely in future updates. This doesn't require any action from an upgrade point of view, table creation will be automatic. However it should be noted that space exports will now no longer include all related workflow information as they did previously.