nmrao yep - I already appreciated the datatypes and that boolean isn't a string so doesn't require the quote marks - I was just didn't notice cos I was overwhelmed with the rest of the groovy - trying to pick this stuff up and teaching myself coding from scratch on my weekends is slow going!
the problem in the end wasn't the type - it was the fact that my jsonslurper line
def parsedResponse = new JsonSlurper().parseText(response)
was wrong - I needed to add in the .text
def parsedResponse = new JsonSlurper().parseText(response.text)
All of a sudden - the star goes blue and I'm smiling! :)