eersfanpilot,
Don't kill yourself trying to teach yourself the systems. Let them teach you that stuff. All I would suggest is knowing your limitations and memory items cold. That's it. (Because that is what 90% of your oral will be over)
My current employer had us do the same thing for our initial, but they gave us the material a week in advance, and it helped out a lot. So I think you're in good shape with 17 days. More than enough time. Good luck.