I guess we're just going to have to agree to disagree on the documentation.
I already have photoshop and I know how to create an alpha channel in that. But you didn't mention I had to do this externally and just assumed I would know I needed to.
Anyway, sorry to have bothered you. I can see the sort of instruction I seek is not going to come from this forum as it seems to be oriented more to those who already have a background in game design. Although I have been using software such as Cinema 4d and photoshop for years, none of that prior experience is going to be much help to me either. Thank you for trying to help though, I appreciate your time