Create an Event Log viewlet in process template

Hello,

I am trying to create an Event Log viewlet in a personalized process template. In order to do this, I added a viewlet in the section Dashboard Template whit this information:

<viewlet>
<preference>
<preference>
</viewlet>

When I create a project area with this process template and open the dashboard in the WebUI, the Event Log viewlet is created but it does not load any information (is loading all the time) and it cannot be edited.
If I try the same operation in the Web UI this works perfectly.

I am thinking that the parameters of the viewlet are not informed correctly but I do not find any documentation of this viewlet.

Any help would be appreciated
Thank you