Symptoms

After the update any SharePoint Event Integrated workflow those not start!
First I have update the K2 Server then I installed the packages on the SharePoint Server and at least I have start the "K2 for SharePoint Configuration Wizard".
A redeploy of a workflow has no effect.
 

Diagnoses

Client is using Sharepoint 2010 Process Event Integration and not SP2010 Workflow Integration.
No event viewer logs occur when adding an item to the list accross all SP ForntEnds.
K2ServiceAccount is site collection administrator.
On the site in the K2 Settings page, the K2 Event Integration Management page showed zero entries.
Redeploying the process adds the event back onto the site and works when an item is started.
Client showed another process and said it doesn't show the item added event...
 

Resolution

The problem was that he selected "Library" events instead of "Library Item" events... Going back and selecting the right category of events resolved this and confirmed again the process works when deploying it again.