Hi Marco,

re:
> Select all objects (solids or surfaces) that belongs to the currently selected edges (and, at
> the same time, deselect the input selected edges)

You can get the selected edges using this:

var edges = moi.geometryDatabase.getSelectedObjects().getEdges();

Then you'll want to loop through every edge something like this:

for ( var i = 0; i < edges.length; ++i )
{
var edge = edges.item(i);
....
}

To deselect the edge you would do:

edge.selected = false;

To get the parent surface or solid of the edge you would do:

edge.getParentBRep();

So putting that all together it would go something like this:

var edges = moi.geometryDatabase.getSelectedObjects().getEdges();
for ( var i = 0; i < edges.length; ++i )
{
   var edge = edges.item(i);
   edge.selected = false;
   edge.getParentBRep().selected = true;
}

Hope that helps! - Michael