Thanks guys.
As implied above, and by the changing title to my thread, I'm backing off the idea of trying to do this ALL in film, although I notice I never quite promised that. I'm doing the POTY for the first time, and definitely trying to do that in film all the way through. There are also various film-based challenges over on the "Film and conventional" forum, that are a lot of fun. Anyway, with the batch nature of film, I'm really finding it hard to do this one on film. My alternate idea for Space for example, would not only have to wait for the light to make the shot, but then for the film to be finished (and really at least two films, since postage is too high these days just to send one), then to send it off to the lab and get it back (2-5 days just for that).
So then I realised I'm not using my X10 at all these days, so I'll try with that and maybe I'll catch up. I'll still use film if there's a reasonable subject and the timing works out, but otherwise I'll probably use digital, and particularly for anything staged or of a kind I haven't done before.