Hi there! I'm applying through camp leaders too and I'm now placeable just waiting on a camp to pick me! They've been brilliant so far absolutely no complaints.
Don't worry about your interview its so relaxed and your interviewer will make you feel very at ease, doesn't even feel like an interview just two friends having coffee! My interview lasted about 45mins then spent another 45mins chatting about films, tv and music with my interviewer so it was very relaxed!