I have a question that no one seems to have asked, In the Cluster Element assignment form you have to enter a CEID (identifier) and CEID digit string (which is the ARS digits dialled route).
When you say you are dialling the CEID + ext number, are you dialling CEID or CEID Digits?
for example CEID = 101 with CEID digits 1101. Its the 1101 that should be entered into ARS not 101.