Shopify should not be involved.
Shopify is involved with every page of Ring's website, it's what controls the shopping cart on his website. Most will probably see Ring's pages contact widgets.shopifyapps.com when the page loads. That being said, the link to the downloadable file on the webpage should not invoke any contact with Shopify.
Going by Joe's first description the lockup sounds like shopifyapps.com merely was not responding, though why that would cause a lockup is anybodies guess these days.
As for Norton, well the less said the better I say.
- Tim