blender transparent textures -> .obj export -> pepakura

So I am teaching myself a bunch of design tools because there are a ton of things that don't exist as models today that I would like to build and release.

But here is the stumbling block I have run into. I am using Blender 2.79, exporting at a .obj file, then importing into Pepakura 4.0.x.

Here is what I do:

*create an object in blender
*assign that object a material (just white for example)
*assign that material a texture that is an overlaid PNG that includes some transparency
*export that object as a .obj file
*import that .obj into Pepakura

When I do this I would expect the texture to be on top of the white material, with the underlying material showing through the transparency in the PNG of the texture.

Instead, I get the transparency rendered as black. So I get the texture image on a black background for that part.

Any thoughts on how to properly represent that transparency in pep or am I running into limitations of either the .obj file format/pepakura/something_else?

Thanks.