PlayHUDNot

Plays a sound or displays a build notification.

Byte
Type
Byte
SubType
Coord
X-coordinate
Coord
Y-coordinate

If type==0 then this is a HUD sound event (i.e. a sound that only the player will hear).  The appropriate values for SubType are available here.  The coordinates should be set to zero.
If type==1 then this is a build notification (the little icons that appear in the top left of the screen).  The appropriate values for subtype are available here.  The coordinates should be set to the location of the event.  The client will use them to determine which location name should be displayed to the right of the notification icon.