Hi Freddix,
Yup it is [was!] an activation problem! Thanks for the pointer.
After installing the 1.062 upgrade, I thought DBP would need re-activating from the original CD - which I now know it doesn't!
This was regressing DBP back to version 1.06 (and maybe messing with other activations?)
Re-running DBProUpgrade62.exe and choosing "Repair" got me back to the latest version. Then I installed eXtends (from clean). I didn't attempt to re-activate DBP at any stage.
And, hey! All is as it should be.
Thanks in advance for what looks to be a very useful set of tools. I'm off to have a play with them now!