Hello, I am an undergrad student who is using ATAT along with VASP to analyze the electronic properties of GeSn alloys. For now, I am trying to get a grasp on how ATAT works and how to successfully run the program. I am trying to do the example in the manual on page 58 for mcsqs where it shows the rdnstr.in file for a CuAu cell. Yet it does not say what the corrdump parameters like the nearest or second nearest neighbor should be, and not what the output would look like. I was wondering if someone would be able to help me see what I should get as an output to double-checkmyself. I can share what I used for corrdump and what it gave out so far in the bestsqs.out file. Thank you! 
Check the original paper of mcsqs: Redirecting
You can try different corrdump parameters, based on your system.