Thanks DataTraveler, but I have just worked out what the issue was.
It wasn’t the ComboBox at all, it was actually the guy behind the keyboard…
My issue was that creating new scripts in the same folder as an exisiting ‘package.psd1’ doesn’t generate a new ‘package.psd1’ file based on the script name. Essentially, I was re-compiling a an old version of the script.
Sorry to waste your time there.