I've just submitted chapter 5, so it should be up soon.
Its a much longer chapter than any of the others, at just over 9000 words and I had thought about splitting it into two chapters. However as I had a few comments about chapter 4 being too short and that it shouldn't have ended in the middle of the action like it did, I decided to leave chapter 5 as it was. I just don't think I'll be writing many more chapters of this length.