Upgrading slimstat doesn't upgrade the tables for a multisite instance.
It upgrades the main site, but ignore the child sites.
Since the last upgrade it looks like a new table as been added because I have lots of "WordPress database error Table 'wp.wp_slim_content_info' doesn't exist for query SELECT content_info_id ...."
[22-Oct-2012 15:42:25] WordPress database error Unknown column 'content_info_id' in 'where clause'.....
After manually making these column and table changes to my instance, everything works as expected. New blogs created after the upgrade also work as expected. Its just the upgrade part for existing blogs that doesn't seem to work out of the box.