An extra space at line 351:
rm -rf /usr /lib/nvidia-current/xorg/xorg
causes the install.sh script to do an rm -rf  on the /usr directory for people installing in ubuntu.
Totally uncool dude!!! The script deletes everything under /usr. I just had to reinstall linux on my pc to recover.
Removing the space will fix this. Probably should do it quickly!!!
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