Newsletter sign-up error

Hi,
when i browse my news
on google crome it shows This XML file does not appear to have any style information associated with it. The document tree is shown below.
and when i browse same on firefox then it works. in other words news shows in firefox not in crome, this is the one issue another issue is
when after that i go to the newsletter sign-up setting in config helper tab and whant to extract the html it shows this error given below-

Warning: DOMDocument::loadHTML(): Empty string supplied as input in /home/brandsro/public_html/realsta.in/wp-content/plugins/newsletter-sign-up/includes/NSU_Admin.php on line 177

Warning: simplexml_import_dom(): Invalid Nodetype to import in /home/brandsro/public_html/realsta.in/wp-content/plugins/newsletter-sign-up/includes/NSU_Admin.php on line 178

Catchable fatal error: Argument 1 passed to DOMNode::removeChild() must be an instance of DOMNode, null given, called in /home/brandsro/public_html/realsta.in/wp-content/plugins/newsletter-sign-up/includes/NSU_Admin.php on line 149 and defined in /home/brandsro/public_html/realsta.in/wp-content/plugins/newsletter-sign-up/includes/NSU_Admin.php on line 227

Please if anyone could help me