Windows 8 has a new feature that prevents new entries to the boot image, etc. Fortunatly there is a way around this.
1. download and install win8
2. downlaod and install easyBCD INSIDE win8
4. Downlaod the Wubi.exe file inside win8, run
5. Open EasyBCD and make your newfound (x)ubuntu the "default OS"
6. Reboot, select (x)ubuntu
7. this will complete your linux install
8. reboot and choose win8