AllowedContent not working

Hi, 

We recently upgraded to 4.4.3 and now our locally developed plugins arent working. 

We have a plugin that inserts custom tags like the below:

editor.insertHtml('<first-page-header>header</first-page-header>');

When we view the source, instead of seeing:

<first-page-header>header</first-page-header>

we see:

<p>header</p>

We have tried setting allowedContent=true in the config.js but it has no effect:

config.allowedContent = true;

We have also tried setting extraAllowedContent='first-page-header'; and allowedContent='first-page-header';

This is out config.js code:

CKEDITOR.editorConfig = function( config )
{
config.extraPlugins = 'first-page-header,first-page-footer,page-header,page-footer,hard-page-break';
config.allowedContent = true;
config.toolbar_Corresponding =
[
['Source','-','Cut','Copy','Paste','PasteText','PasteFromWord','-','Print','SpellChecker','Scayt'],
['Undo','Redo','-','Find','Replace','-','SelectAll','RemoveFormat'],'/',
['Bold','Italic','Underline','Strike','-','Subscript','Superscript','NumberedList','BulletedList','-','Outdent','Indent','Blockquote','JustifyLeft','JustifyCenter','JustifyRight','JustifyBlock'],
['Link','Unlink','Anchor','-','Image','Table','HorizontalRule','SpecialChar','PageBreak'],'/',
['Styles','Format','Font','FontSize','-','TextColor','BGColor','-','Maximize','ShowBlocks'],
['first-page-header', 'first-page-footer','page-header','page-footer','hard-page-break']
];
config.toolbar_Full =
[
	['Source','-','Cut','Copy','Paste','PasteText','PasteFromWord','-','Print','SpellChecker','Scayt'],
        ['Undo','Redo','-','Find','Replace','-','SelectAll','RemoveFormat'],
	['Checkbox','Radio','TextField','Textarea','Button','ImageButton'], '/',
	['Bold','Italic','Underline','Strike','-','Subscript','Superscript','NumberedList','BulletedList','-','Outdent','Indent','Blockquote','JustifyLeft','JustifyCenter','JustifyRight','JustifyBlock'],
	['Link','Unlink','Anchor','-','Image','Table','HorizontalRule','Smiley','SpecialChar','PageBreak'],'/',
	['Styles','Format','Font','FontSize','-','TextColor','BGColor','-','Maximize','ShowBlocks'] 
];
config.toolbar_Basic =
[
    ['Bold', 'Italic', '-', 'NumberedList', 'BulletedList', '-', 'Link', 'Unlink','-','About']
];
};

This is our plugin code:

(function()
{
	var a ={exec:function(editor)
		{
			editor.document.createElement( 'first-page-header' );
			editor.insertHtml('<first-page-header>Insert first page header text here</first-page-header>');
		}
	},
	b = 'first-page-header';
		CKEDITOR.plugins.add(b,{
		init:function(editor){
		editor.addCommand(b,a);
		editor.ui.addButton('first-page-header',{
		label:'First Page Header',
		icon: this.path + 'first-page-header.png',
		command:b
	});
	}
	});
})();

Any ideas what we're missing?

Thanks, 

Peter