Thanks. One problem, however.
This is the first time I've used any unincluded extensions. I've imported both Multitudes and Conditional Backdrops.
The problem is, when I followed the example in the documentation:
Gravel is a multitude.
...I get a compile error.
Problem. The sentence 'Gravel is a multitude' appears to say two things are the same - I am reading 'Gravel' and 'multitude' as two different things, and therefore it makes no sense to say that one is the other: it would be like saying that 'Laurel is Hardy'. It would be all right if the second thing were the name of a kind, perhaps with properties: for instance 'Blue-Ridge Mountains is a lighted room' says that something called Blue-Ridge Mountains exists and that it is a 'room', which is a kind I know about, combined with a property called 'lighted' which I also know about.
Am I meant to use some sort of include/import? I assume I don't need to.