That will create a monster. If the staff is going to be hidden, why do it? If you want to stop "line overflows", pick a paper size, margins and staff metrics that are consistent with the music. NWC 2.5 has changed the piano (and other) templates. To see them, existing templates must be deleted and NWC 2.5.1 reinstalled.
This little User Tool might help:<?php
// rg_Squash.php ver 0.90; insert Spacers
// Ref: http://my.noteworthysoftware.com/?topic=8003.0
require_once("lib/nwc2clips.inc");
$skip = explode('|', 'Fake|Context|Spacer');
$add = explode('|', 'Bar|Note|Rest|Chord|RestChord|Clef|TimeSig|Key');
//
$clip = new NWC2Clip();
echo $clip->GetClipHeader(), PHP_EOL;
foreach ($clip->Items as $item) {
$o = new NWC2ClipItem($item);
if (in_array($o->GetObjType(), $skip)) continue;
echo $item;
if (!in_array($o->GetObjType(), $add)) continue;
if ($o->GetTaggedOpt('Visibility') == 'Never') continue;
echo '|Spacer|Width:0|Color:1', PHP_EOL;
}
echo $clip->GetClipFooter(), PHP_EOL;
?>