Hi Larry, so in v4 there's a mechanism for the Esc key to interrupt scripts that could be spinning in a long lasting loop. The way it's supposed to work is if you hit escape and it has been a while since the script entered an event loop it will try to force the script to exit by throwing an exception for any function calls. But in the Jan-22 beta this mechanism gets triggered a little too easily, it's been tuned up for the next beta.

I'm not sure if that's exactly what you have run into but if it is it should behave better in the next beta.

- Michael