Pathpilot version 1.7.2 (which you are using) was released on 15 April 2015.

The RapidTurn product was released in June 2016, and a new version of pathpilot was released to support RapidTurn at that time.

Like others have said, update RapidTurn!

I would strongly suggest you go to the current version, which will require you to buy a USB stick from Tormach (version 2.0 and above installed a new Linux OS, and required an install USB stick for that).