Hello
I am not sure which monitor is delivered with the board you are speaking about.
As far as I know CodeWarrior does not support Serial monitor for HCS12X.
We support Serial Monitor for HCS12, but we only support (validate) connection to Freescale serial monitor.
I do not know what Tech Arts provides as monitor, but I am not sure it uses the same protocol as the Freescale one. Additionally as the whole debug module has changed between HCS12 and HCS12X, debugger will not be able to handle breakpoint in flash on HCS12X.
If you are looking for a low cost debug solution on HCS12X I would recommend you to look into TBDML connection.
I hope this helps.
CrasyCat