Hi Dean,
Everyone at REX is lovely, it's a great place to work.
Make sure you study every night for the tests the next day. During EP's make sure you have a group study session with others in your ground school, I found this invaluable.
Also make sure you know your two PA's that were sent to you with your starter pack, one less thing to memorise.
If you put in the work it will pay off.
Also remember it is not all about the exam marks, make sure you show your personality, they are also interested in how well you interact with trainers and fellow ground schoolers.
Good luck, let us know how you go.