Prelaunch
Programs configure their questions for the next cycle in the Liaison prelaunch environment. Once the general CAS questions (that is, the items in sections 1-3) have been certified/approved/whatever they do by the relevant professional association, it is possible to create test application and submit it. These are detailed notes with screenshots about the process to do that; the example is in Vet, but the process is similar across all CASes.
...
Note that retrieving an unsubmitted application will be quite unsatisfying--the available fields are quite restricted.
Postlaunch
There are several different options for testing the data mapping and confirming that data is being imported correctly.
In Slate, there is a group of queries that return data from imported files, which can be compared to the same data in VMCAS.
