There is a class named TestResult which has getter methods for TotalPassedSteps, TotalNumberOfNotRunSteps, Result status, StartTime, Duration and many more.
You can use an object of that class to write all these methods into a custom file of your own.
It works for me! :-) Attached is the method which I used in my TTS scripts to generate the result file. You can check it out.
Also, there is a telerik documentation link explaining the same: