Ok, to render something, you need to pass the mesh itself, normals and some other params, don't remember the exact things. It's up to the user in which order to pass them. But you need to tell Dx this. Just look at the Dx9 SDK exemples

Second, irrlicht uses it's own formats, you have to create a blank modell description in irrlicht and fill it with the data returned from A6, like that user allready said. You need to know both, the irrlicht and the dx mesh format to convert it. But I'm sure someone has allready done sth like this.

Provide some code and I'll tell you what I would do