As mentioned, Haemaria/Ludisia does tend to ramble. IME it is quite flexible with regards to media. I've used straight potting soil before and it did okay. I've also done straight sphag before and again it's done okay. For me it seems to do best in a mix of garden soil amended with large grade charcoal, hydroton, and either bark or coconut chunks.
Yes, Andrew, if you lay a stem down so the nodes are in contact with the media or slightly buried it should root. I generally just chop the stem off, give it a day or two for the end to callous over and then pot it up. Keep the media lightly moist and the cuttings in a warm shady spot.