No, 1 poly with 24 surfaces
There's one material for each surface
Sorry I'm confused now... there is no way to have 24 materials if you only have one surface...
they're all transparency enabled
This may be what causes the rendering issue. Besides, your model doesn't show transparency, you could have used an opaque material. In Minecraft, that's what happens. If pixels are transparent, they are actually discarded with alpha scissor.