@BlackMaple good evening, great photos of your new collection. Nothing to worry about IMO, yours are looking very typical of maples this year and especially in August. The heat has taken it's toll on many across Europe, with many losing their leaves completely. Very glad you have the Vertrees book, it is full of very useful information and regarding individual cultivars. Do try and make sure that you water only when needed. Potted maples can suffer badly from being over watered. Always check the soil before you water and not carry it out because your diary says it's watering day. Rule of thumb, if dry water if wet then don't. Nothing to worry about with your Bloodgood IMO, just heat and moving stress. Next year you will see your trees as they should be. Just to add, garden centres and nurseries never look after them as we all do at home. This is why I have found that around 2 years after I have purchased a maple is when they start to look a lot better. Look forward to seeing your Autumn display.