Glad it worked!
Try reinstalling both Cool term and Download the Virtual Comm Port (VCP) driver for OSX from the FTDI Drivers Page. and reinstall that.
Reboot computer.
This happened to me once and never again. Not sure if it is a bug or fluke.
I tried that code on the tiny G and it seems to be working perfectly. I tried the file using both coolterm and Tgfx several times, no errors of any kind.