Mesh areas not being transparent like they should

[Phaenoh]

I've created this cute little windmill and for the fan blades I borrowed the mesh and textures from the hot tub. It had a lattice area. I've made the area its own subset like it needed, but for some reason the holes between the lattice slates are solid black. What am I missing?

[HugeLunatic]

So what I thought was the issue appeared to not be the issue, or maybe I did it wrong. There is no MMAT for the windmill_mask. The AL Bohemian bed is similar to this, in that it has subsets not recolorable but are linked to the same texture as the recolorable parts. And they have transparency, don't know if looking at that will help you out.

btw...this is adorable!

[Phaenoh]

Turns out the transparent part's shape was point at the wrong matdef. All fixed now, hurray!