I've installed Ubuntu 14.04.1 LTS on my Macbook Pro 15" with Retina Display with Parallels 10. Unfortunately the whole GUI is very small so it isn't very comfortable to work with.
A fix for this problem: http://www.itworld.com/software/415502/scale-title-bars-and-menu-ubuntu-1404
Sadly it does not work on my installation. I can regulate the slider to my preferred size but it doesn't have an impact on the appearance of Ubuntu.
Maybe someone has an idea, how I can fix this. Thank you very much!