The hud doesnt fade out because there is no "state=12" action.
state=12 never gets called.
Could look like this:
:state=10:timerstart,hudshow=second,sound=audiobank\user\messagebleep.ogg,state=11
:state=11,timergreater=1000:sound= ,state=12
:state=12,timergreater=5000:hudfadeout=second,state=13
(there is still a sound source missing in state=11)
You can add the scancodekeypressed thing like that:
:state=10:timerstart,hudshow=second,sound=audiobank\user\messagebleep.ogg,state=11
:state=11,timergreater=1000:sound= ,state=12
:state=12,timergreater=5000:state=13
:state=12,scancodekeypressed=45:state=13
:state=13:hudfadeout=second,state=20
Hud fades out when state=13 is true.
state gets set to 13 when timer expires
or key gets pressed.