Hi Joe,
Yes, exporting layers is planned. Also, a public online library where users can share their raster and paths layers for others to use in their projects. As far as exporting though raster-layers will be able to export to common image formats and I haven't fully settled on what the situation will be for paths-layers yet. PixelCNC will definitely allow exporting a paths-layer as an SVG but I'm not completely committed to adding DXF only because it's a bit more complicated of a file format. If someone ends up needing it I'll probably put the time aside to tackle it though but hopefully everyone will be able to manage with being able to export paths as SVG files.
In the meantime a small workaround that might be useful is to just hide all of your other layers and then export your canvas as a heightmap image, which is almost the same thing as exporting an individual layer, except that it will be the dimensions of your canvas rather than the layer by itself.
- Charlie
EDIT: I forgot to mention that the online asset library will be built into PixelCNC itself, as opposed to something that's used within a web browser.