In reply to John Kelly:
The one that we stopped at "Zasavska koča na Prehodavcih" only had a water supply from a spring 10 mins walk away.
The issue with the toilets was maintenance as much at anything I think, the base was open so that the draw from the chimney wasn't drawing air into the cabin and down the pan as it is supposed to.
If you got to places like New Zealand, where they've made a massive push to install toilets everywhere it seems, they are fine and the only smell if the vent is blocked or damaged.
The snow we met wasn't covering everything, we were just planning on a route going north from the hut and around the north of Kanjavec which was particularly snowy and the alternative would have taken us to a very busy hut because I think Koca na dolicu was colsed and also I'd had a fall and we were running out of days.