Thanks for the reply and assistance. This works and is close, but not really what I am looking for. As I have multiple ajax updated outputPanels on my display concurrently, I only want to grey out a single one at a time (i.e. NOT app modal behaviour).
The following snippet is a bit closer to what I need than what I posted earlier, but is still not quite there.... Is there a better way to achieve what I looking for = i.e.non-app modal gray out of a outputPanel during ajax operations that update it?
<a4j:status id="mainStatus" forceId="true"> <f:facet name="start"> <t:div style="position: absolute; top: _toppx; left: _leftpx; z-index: 500; width: 100%; height: 100%; background-color: #CCCCCC !important; opacity: 0.5; -moz-opacity: 0.5; filter: alpha(opacity=50);"> <h:graphicImage value="/images/ajax-loader.gif" style="position: relative; top: 50%; left: 50%; opacity: 1 !important; -moz-opacity: 1 !important; filter: alpha(opacity=100) !important;"/> </t:div> </f:facet> </a4j:status>