This message is to serve as an update to this thread. @sfehmi was able to provide access to the dashboard which allowed us to troubleshoot the issue in her installation.
The issue was determined not to be related to a bug in the Pegasaas plugin, however because the page (when rendered via the WordPress system) did not include a </head>, <body>, </body>, or </html> tag, the Pegasaas system that creates a Critical CSS snapshot was unable to parse the page, and subsequently could not provide an optimized page.
We were able to identify that, in this particular theme, the “Clean Page” layout, which exists to display a page without the top navigation and footer, was missing key elements.
The layout included a misplaced “wp_head()” function, which was not wrapped within the proper <body>…</body> tags. In addition, the layout did not include any call to wp_footer() or get_footer().
The solution was to code the layout, much like the other layouts included with the theme, but hide top navigation and footer regions with CSS.