Is it possible that your reports were produced using different versions of the Narrative Report?
I shall be removing the SVG check in my next release and also the PDF facility. PDF images were only added as a stopgap measure to overcome lack of SVG rendering in some browsers but had their own problems according to which browser was being used and which PDF reader was the default.
The current report does not function correctly when published to local disc rather than a web site. I am attempting to address this issue before releasing the next version.