Symptoms
How to use k2 designer connect to mssql retrieve data? The service instance was not found in the service object explorer in k2 designer.
Diagnoses
The "sql server service" service type was not registered yet, along with the service instance to connect to their mssql database.
Resolution
A document was provided which included the steps on how to connect to their mssql database from the smartobject service tester and after which create the smartobject to be used in their smartforms.