Hello, and welcome to the forum.
Are you attempting to use the 8-bit MCU version or the 16-bit MCU version of CW? Since you have posted in the 16-bit forum, and the MC9S08QG8 is actually an 8-bit device suggests that you might be using an inappropriate version.
You will probably need to download the latest (8-bit) version of CW, or install updates to an older version, so that the device is supported (although the QG8 is not new, and has been around for quite some time).
Regards,
Mac