Hi Dave, thanks for that. There aren’t different firmware versions for the Xbee S2C modules. Just as an update - I couldn’t use the Xbee S2C as a dongle. Maybe it needs it’s own driver as mentioned here (Kinds of Zigbee Dongles)
edit: update to the above; I got the Xbee S2c to work as a dongle. It was a problem with my Xbee explorer (https://www.sparkfun.com/products/11812). This one has a serial device of 0403:6015. I got it to work with an older Xbee explorer (https://www.sparkfun.com/products/retired/8687) which has a serial device of 0403:6001 - and what the zigbee adapter code is looking for.