OK.. changed all my partitions apart from the boot (er, of course!!) to logical with Partition Wizard. Instant and no problems. So now the issue of my boot drive not being Disk0 is no longer one? (An issue!).
Just one thought. If you make an image backup of a primary partition, with Win7 native, or Macrium and install into into blank (unformatted) space, do you get a formatted, primary partition, as the original.
Assuming the partition must be formatted first, will copying a primary boot partition image onto a logical drive make that partition primary after the install. In other words, do partition images take with them the attributes of the partition from which they were made?