Sorry for the confusion, the documentation was incorrect – I’d updated the readme.txt but not the documentation page. It’s corrected now.
The mashup click setting is global, as you noticed. All mashups must have the same behavior.
<div id='hiddenmap' style='display:none'> [mappress] </div> <a href="#" onclick="jQuery('#hiddenmap').show(); mapp0.resize();">Click to show map</a>