Reporting back here after trying the Hobson's drag choice for dynamic partitions in Macrium Reflect. Three dynamic partitions, including System, dropped into the new SSD, but the C: boot dynamic partition 'copied' only a phantom partition, i.e., it was empty.
Then, following a tip from my supplier, pp.co.nz, I tried EaseUS Partition Magic, the now Chinese-owned old programme, and without any fuss, like dragging partitions, it worked like a charm. All four dynamic partitons migrated, and in the process had been converted to Basic partitions.
I highly recommend reasonably priced EaseUS Partition Magic, not only for the efficiency of the software, but also for the efficient, polite way in which the company's Help desk dealt with...