Hi Graham - that's a relief - thanks for clearing that up.
The brick versions shouldn't be too far behind as I've managed to get the configs for the second one almost right and it's working in game albeit with a couple of anomalies which I've already traced and have virtually sorted. Once you have the second one, I'll give you easy instructions for repairing the weld by copying and pasting the corrected mesh from one of the brick versions into the stone - they all share identical mapping, so it's an easy swap.
In any case, most factories developed piecemeal as business progressed, and as often as not later additions were in other styles and materials - I'd always intended that the packs should be mix-and -match rather than all the units necessarily just coming from one set. When I have enough different ideas for the second group, it's likely that they'll tend to have variants of the existing textures as well as close copies, to add more variation, Don't forget that you can drop the units down by a floor to expand the variety, too....
Lastly, thanks for your continued interest!
Cheers,
m