Explicit Export to SharePoint Lists
With this approach, you can use an SVAdm operation to update your SharePoint status lists with the data as it is currently.
To explicitly export workflow data to SharePoint:
svadm -o updateprocessstatuslist -url <URL to the root site to export> -statusurl <URL to the status lists you created above>
-statuslist <name of the process status list you created above>
-recurse
svadm -o updateassignmentstatuslist -url <URL to the root site to export> -statusurl <URL to the status lists you created above>
-statuslist <name of the process status list you created above>
-recurse
These SVAdm operations will take a current snapshot of all of the workflow data starting at the specified site and going through all subsites (if you want to do only a single site without the subsite or subsites, omit -recurse). It is safe to run these commands multiple times against the same SharePoint status lists. If an entry already exists for a process or assignment, it will be updated, not duplicated. Duplicate entries are not created for the same workflow objects.
The advantage to this approach is that you do not need to modify any of your workflows to export your process data. The downside is that it is not automatically kept in sync. Running these commands takes a snapshot of the system's state at that time. However, in practice, real-time data is seldom really needed for reporting purposes, and it is often sufficient to set up an automated task that runs the SVAdm operations on a schedule, and then run reports against that snapshot.