OK so I made two ;-)
Was pretty straightforward from the instructions given on the original site. It's a very well-designed shell for the parts, and my earlier doubts about the battery being loose in the frame were unfounded as I didn't read properly: it is held in place with glue between its 'wings' and the frame.
A few minor comments:
The areas on a new print that catch inside the MZ-NH1 casing are the '+' and '-' characters, which were printed raised a bit too high. Easily reduced with careful sandpapering.
The new LiPo battery's original orange sellotape, that cover