amaniel b) SHIPPING CALCULATION
ON Check-out page when clicking to calculate the shipping costs there's an odd toggle overlaying. I've checked the demo and it looks different. Could you check it out?
Sounds like it may be an issue with a 3rd party plugin you have or customization, also there might be a plugin conflict with a 3rd party plugin – you can check that by disabling then reactivating a plugin one at a time to see if you find a conflict there.