Help please creating a custom product type in Magento 2

[iweb_smartie]

What you will find is a lot of tutorials (including my own) make an assumption that you will either create a new module or have a module already that you are just adding to.

[newtomag2]

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