Hello Andy, since the demo (same files you downloaded) doesn’t have this issue, we have to figure out what your issue could be, we have to check some things first: is the theme installed correctly?, is it configured in System>Configuration>Design?. Also, did you modify the theme files?, may be extensions installed?.
First of all I don’t think I have made an modification to the theme which would affect this. I have a few extensions installed which are Meanbee_Royalmail Shipping Extension and also DisableProduct but this was installed after I reported the issue.
As for the configuration, I have the following filled out in System>Configuration>Design:
Current Package Name: default
Skin (Images / CSS): hellominty_pink
Everything is set up either blank or default applicable to the store itself?