The interview is with a COPA captain and a girl from Human Resources. They don't ask you anything rare, just a few minutes talk; what do you think about COPA, why COPA, Why do you think they must hire you...and things like that. Then you have to show them some of the original documents.
The COMPASS test is on a computer and you have to do 6 diferent test including 30 ATP questions most of them referred to big jets. Some of similar test you can find it on this page
Computerized Pilot Tests-Latest Pilot Jobs
The psychological test it's also in the same computer and you have to choose one of the two options of common sentences, and are 225 questions.