How to add a custom field to the CKEditor download dialog and pass this input to a custom download page

Question

I am using a standard CKEditor instance and trying to add a custom field to the UPLOAD dialog so that the user can enter the size at which they want the file to end. I used this to get the field in the dialog;

if ( dialogName == 'image' ) { var infoTab = dialogDefinition.getContents( 'Upload' ); infoTab.add( { type : 'text', label : 'Desired Width (pixels)', id : 'imageWidth', name : 'imageWidth', 'default' : '600' }); }; 

The field is in the download dialog, but it is not transmitted in the form; when it is submitted, it is not transmitted in the request or the collection of forms.

Does anyone have any ideas..?

thanks