You're welcome. It's a very useful program, because not only can you use it to scale armor pieces (it also has snap points, though sometimes you may need to manually reposition parts), you can also use it to scale props. It also has a number of convenient features, including the ability to do non-uniform scaling (which I had to do for my Colonial Marine breastplate - it was bulging out too much in the front and so I wound up having to modify it to be a bit flatter against my torso) and then be able to export the modified model. It's really cool and really handy.
The one thing to be aware of is that at least in some cases (i.e. mine), helmets are (very) difficult to scale properly, even if you have your exact head circumference inputted. I was trying to print an ODST helmet, and I had to print the bottom half at least three times before finding a size that actually fit my head, but even that was too big. For helmets, or at least for the one I was using and my larger-than-average head, it's pretty much trial and error, due to how the head model isn't the best.
Don't let that discourage you though - for everything else, Armorsmith is fantastic and works perfectly fine.