Resolution: Cannot Reproduce
I have the latest stabile release of STK called 184.108.40.206-pl1.
When I tried to test ERK tool, I received an "Undefinned offset: 2".
The tool "told" me to click "here" to reload the ERK tool, but when I tried to reload ERK again, I received this "offset", again.
Here's an image with message that I received.