Hi Rick,
A few things to look at here , however I'd suggest you contact Sophos support directly , either via phone :
Contact Sophos technical support - Enterprise solutions
Or via email :
Support query form - Sophos
From the screenshot you have posted I can see two problems :
1) The date on the install.sh is the 8th of may , the latest install.sh file from the Sophos website is dated 23rd of July so it may be your trying to install an old version
2) When you've typed 'install.sh' that doesnt mean your running the installer from the directory your currently in , you may be running any other install.sh script which is found earlier in the path on your machine.
Running '.\install.sh' or {full path}\install.sh would make sure your running the correct file.
Regards,
Sophos Support