Max, thanks.
I tried running Cycles as admin, but not MoI - I'll give it a go. In any case, a snapshots folder outside the Program Files folder is much more preferable - looking forward to that, thank you.

Mauro,
Doh! Sometimes, even when seemingly hard-wired to the net, I overlook using a search engine to make up for my poor language skills. Thanks for educating.

Here's a bit of trivia: rather coincidentally, while I was learning/working on a MoI script earlier today, I thought, 'Where does the word 'factory' actually come from?" Searching for "factory etymology" shows the Latin factorium is literally, ‘oil press’; the English language makes more and more sense all the time, after discovering its roots. :)