Notes from a recent Sage 100 2017 install:
(1) Just because the installer says the license keys don't include payroll doesn't mean it's true. Proceed and check the Payroll Subscription Expiration date in System Configuration, modules. If it says FAIL, go to the registration tab, click Edit, don't change anything, and click activate. then check the Payroll Subscription Expiration date again.
(2) Make a copy of the fresh install before running migration. If the customer is using Webroot AV, make them turn it off. Xcopy error and most of MAS_System is gone...