I'm trying to add in a way to store data about different sites a customer may have. This is my first development, so the theory was to keep it pretty simple for now.

Managed to code the model which seems to work ok, if I import it without any xml files no errors and my extra fields show up.

pastebin.com/ih5W2qca

Then I get to coding the view, which I have to admit I don't understand that well. I thought I'd start with tree view. the following is the closest I think I've come.

pastebin.com/XnyA5FWA

When I try to install the module with this xml it throws an error.

pastebin.com/hAy0gXen

I really have no idea how to proceed. Been trying to get a view working for the last 5 hours.