What is the difference between a master portlet and a user portlet?
User portlets are the visible instance of a master portlets. It holds its own properties, which overrule the master's properties. Master portlets can only be viewed in the Portlet-Designer. Very few properties can be overwritten by the user portlet, such as the height of the portlet. Use the Icon in the design portlet header:
Operator [TIS]Board - Adjust Portlet.