Project packages out in Windows and works but HTML5 doesn't work?

Hi,

I have created a vehicle configurator for a client. They want to put the project on their website so that anyone with any device can use it. When I package it and launch it for Windows, it looks and works perfectly. When I package it and launch it for HTML5 I get the error in the screenshot provided. I am not a coder or programmer. Is there a way to get it to work as smoothly as it does for Windows onto the website without compromising the quality of the project? Please help!

Sarah