@d-healey Ahhh.... that didn't work. But just looking at the file structure. I've spotted the issue. I have all my main project work in folders with an underscore at the beginning (just how I've organised my folders forever!). Hise doesn't seem to like that underscore. I've dragged the project folder onto the desktop and it's built! 9 times out of 10 these kind of things are either a checkbox, or a stray underscore or space.

Thank you both for the supportive introduction to the community. I'm looking forwards to the journey ahead and with less underscores.