Answer by David N. ·
If there is no inter-tier time displayed in the column then it means that the web service didn't cross to other tiers within your application structure.
You can go to the transaction flow dashlet and right click on the tier where you know the web services should originate from, then right click and drill down to web services. This will show all the web services related to that tier and any latency related to them. You should not have to do any further configurations to see this data.