Darek,
If you are using the latest plugin, there is a Notify message tab in the configuration dialog that is capable of sending any command to the controller (Such as TE) and load the result in a DRO. You can attach the command to a button with the VB NotifyPlugin() function. Or you could use the error signal in a MACRO to send the notify message to get automatic error codes.
I might add the position error settings into the plugin configuration dialog. But right now, it is considered like the tuning parameters (KP, KI, KD) and offset voltages (OF), something to be set and burned into the controller.
Steve