Well, that's something of a relief for me, in that it seems I may not be going senile just yet after all.
Curiously, it shows on my Vista machine as installed, but not on my XP machine, which I was looking at, as I believe Kaz runs XP.
I must have originally used the 'no-installer' version, which updates as it is. If the 'no-installer' option is no longer available, this is where the confusion lies.
Perhaps it's one of those programs which prefer to run off the 'C' drive, and give no option?