It's now working! Thank you!
The only thing I'm confused about now is the capitalisation of folder structures. When I look at directory structures vs model names, I seem to be seeing some inconsistencies (both in the code in my version of 2.2 and in other articles). Presumably it doesn't actually matter whether I choose .../Model/... vs .../model/... as long I'm consistent and my settings files etc point correctly the right folders?
Thanks again, you've stopped me banging my head against a brick wall - now a brief lull before I hit another problem