A 127 exit code typically means a command has not been found.
If you look through the log you pasted, you can see:
11:43:54 AM: Executing user command: hugo_0.46
11:43:54 AM: /usr/local/bin/build: line 32: hugo_0.46: command not found
Since I don't know your setup, I can't say for sure, but I would venture a guess that you have hugo_0.46
set as your build command, when the build command should be hugo
and the version set in the Build environmental variables section (per the post to which you linked).
I describe this in more detail in the post here: