[ubuntu] Ubuntu 14.04.2 not working on Macbook pro 12,1 (Early 2015)

I tried to live boot into Ubuntu using a bootable USB but whenever I do, there are always problems with the GUI. The dialogue boxes would be empty, and whenever I open terminal the text would be all messed up. When I click the settings button on the top right corner, the box shows up but it's empty. Here is a picture:
I read that others have gotten 12,1 to work with 15.04 but I would prefer to use 14.04. The same USB does not have any problems on 11,1. Any tips?

Thanks