Glad to see you're still at it Richard! I'm sure you'll continue to improve. I sometimes get stuck on a plateau for what seems like forever, then suddenly it falls into place.
Tomorrow is my first pool meet ever, and I'm just going to approach it as a learning experience.
Are you doing any flexibility exercises or strength training in addition to swimming? That might help with the arm problem. When I do weights (just once a week for now) I first do the chest fly machine (for pectoral muscles) facing forward, as normal. Then I sit on it facing backwards, lower the weight down to about 10 pounds, adjust the handles so that they are far back as they'll go, then grasp them and pull outwards and back to get those muscles between the shoulder blades. This can also be done lying face down on a weight bench, using dumb-bells.