Hello Lauren,
Regarding your International zone, you didn't follow the 2nd point :
- Create a custom shipping zone via "Hikashop->System->Zones"
- Add every countries different than your local country in that shipping zone
You don't have any sub-zone in your international zone, so any of your shipping methods which have that zone as a restriction won't be available.
You should add every countries different than your local country in that shipping zone.
However, even when I set shipping within the USA to "$0," shipping still isn't free within the USA. I'm using the USPS extension.
If you want a free shipping method then you should use a manual shipping method instead of the USPS shipping plugin.