Hi,
You won't be able to use the TestStand API within the .exe, since there isn't a way to pass the SequenceContext into your executable. You can use the Call Executable step and determine if the .exe passed
or failed by the return value of the .exe. Your other option would be to use
the .NET adapter to call the executable. Take a look at both of these options and let me know if you have any questions.