[PalmNut]

Nice piece of work.

I'd also modify the quick reply HTML and JavaScript so that the input field is disabled if threading messages until a message is selected. Like so:

Edit the showthread_quickreply template by adding a new attribute to the text input field.

Find:

<td><input type="text" class="bginput" style="width:600px;" name="nowplaying" value="$post[nowplaying]" size="50" maxlength="85" tabindex="1" /></td>

Replace with:

<td><input type="text" class="bginput" style="width:600px;" name="nowplaying" id="qr_nowplaying" value="$post[nowplaying]" size="50" maxlength="85" tabindex="1" /></td>

Edit clientscript/vbulletin_quickreply.js as follows:

Find:

if (WYSIWYG != 2)
  {
    fetch_object("qr_message").disabled = true; // message textarea
    fetch_object("qr_message").value = must_click_message; // message textbox

Below that, add:

fetch_object("qr_nowplaying").disabled = true; // nowplaying text

Find:

fetch_object("qr_message").value = "";

Below that, add:

fetch_object("qr_nowplaying").disabled = false;