Pixel only exports visible layers when submitting to rodan

If a layer is completely invisible when submitting a folio corrected in pixel to rodan, that layer doesn't get exported and the resulting file is empty.

(For example, I forgot to make layer 2 (staff layer) visible before submitting to rodan. In the resulting files, the background file clearly showed that the staves had been removed, but the layer 2 file showed nothing at all.)