You don't indicate in which country your route is in. The procedure in the UK is as follows:
Make sure that AWS ramps are placed before the signals. Then, in the Edit Session box,
select the 'AWS Configuration' option. This will provide an AWS box in driver. When you
drive the session, if the next signal is set at clear (green), a bell will sound in the cab when
the loco passes over the AWS ramp, this is normal practice, and no action is required from
the driver. If the next signal is set to caution (yellow), or danger (red), a buzzer will sound
in the cab, and the driver must acknowledge it by cancelling the AWS. This is achieved by
clicking on the cancel button in the AWS box on the screen. The 'insert' option of cancelling
the AWS only seems to function in sessions which come from Trainz installed routes.
Regards,
Dick.