@bimi, Welcome onboard! 
I’ve just had a quick look and your iWeb site looks like it is built for desktop only. Sparkle on import defaults to 960px and your website doesn’t work on that breakpoint so I’m thinking that is the reason behind parts of your site missing on import.
@duncan, the owner of Sparkle, might be able to help you further if you email him on feedback@sparkleapp.com?..