Sorry @Marc Stridgen, one thing I've just noticed - font icons aren't working:
Presumably this is related, due to the missing "www" in the URL of the font (typing the below into my browser downloads the font, but presumably the URL forwarding is kicking in).
https://zero88.com/forum/applications/core/interface/font/fontawesome-webfont.ttf?v=4.7.0
In the template, this is just listed as:
href="{url="applications/core/interface/font/fontawesome-webfont.woff2?v=4.7.0"
How do I change where this is pointing? The only place I can find the URL within the AdminCP is within the licence. In the client area, I can't change the URL to include "www", as it says "There seems to still be an installation of Invision Community at the URL on file. Before you can change the URL, you must first remove the existing installation."