Hi,
I had problems with the above info pertaining to entering a known extension. It didn't work for me. I worked it out and here is what I ended up with:
Custom App named: "enter-extension"
include => internal-presets
include => extensions
exten => s,1,Set(TIMEOUT(digit)=5) ;Digit Timeout 5 secs
exten => s,n,Set(TIMEOUT(response)=10) ;Response Timeout 10
exten => s,n,Background(usergreeting0002)
exten => s,n,WaitExten ;Wait for an extension to be dialed
exten => s,n,Goto(enter-extension,t,1)
exten => i,1,Playback(pbx-invalid)
exten => i,2,Goto(enter-extension,s,1)
exten => t,1,Goto(extensions,${SYSOP},1)
exten => t,2,Hangup
Remember to change the recording (Background) to meet your needs.