Success! I finally managed to solve this little puzzle. It didn’t take too long actually.
First, I had to update the Intel OpenCL runtime framework on my host machine which went with no hiccups.
Second, because I installed the latest Hashcat release I also had to install the latest Hashcat-Utils to convert the .cap file to the new format Hascat is now using which is .hccapx.
Voila!! I then ran Hashcat using the formula in your book and its now working perfectly although I am going to have to stop it now as its getting late but I’m very impressed with its performance.