Andy, there should not be a gap between the nose block and the deck. I don’t have the build manual handy right now and it is difficult to tell from this photo what the problem is. The king plank should rest on the center frame and end at the nose block. It is not clear, but you might have trimmed down the nose block too far along with the toe railings. There should not be a gap between the deck and toe railings. Could you post more pictures?
I agree. It looks like you need to trim back the “king plank” so it drops behind the nose block, although it’s not totally clear from the picture you posted. This assumes that the deck in the picture is properly aligned front-to-back.
Epoxy in some wood pieces where the screws for the handle will enter to ensure that it’s strong enough. I added a 3/4 x 3/4 scrap to each side of the center frame but bigger than that might be better.