API V8 - how to add new routes

We are trying to customize the V8 api using the extension framework but it is not working as expected.

We are adding new routes in custom/Extension/application/Ext/Api/V8/Config/<route_name1>.php, <route_name2>.php

The expected behaviour is that on Repair and rebuild the files in Extension folder should be merged into the custom/application/Ext/Api/V8/Config/routes.php file

But this is not happening .

Please guide us if there is something we are doing incorrectly or is the a bug in SuiteCRM

I have same problem. I have a this error below:

But the controller is already there.