DE0-nano-soc demonstration code won't build, fatal error: socal/socal.h: No such file or directory

I'm getting up to speed on the DE0 Nano SOC development board. I've downloaded version 1.3.1 of the system CD, and I'm working through the examples in the user manual (attached)

On page 60, when I try to build the example, I get an error that there is no file or directory called "socal/socal.h". I've searched the entire system CD and can't find it elsewhere. Am I missing something?

Here's where I downloaded the system cd:

http://download.terasic.com/downloads/cd-rom/de0-nano-soc/

Edit:

On 2019-11-11, a new system CD was released (1.3.2). This problem was not fixed.