I've now had my hut for a year and it is a couple of hundred metres from my house and so I am still able to use it during lockdown. Lucky me!
Here are a few things I have observed over the year about water collection, toilets and lighting.
The swanky metal gutters and down pipes are lovely and were very easy to fit aparently. There are no pre cut holes in the gutter lengths which allows choice about where the down pipe is placed. Murray the joiner drilled several small holes instead of cutting one big one to stop leaves etc getting into the waterbutt. But they block too easily so going to have alter that. I have heard of various methods of keeping leaves out including plastic spikes and pot scrubbers. For now, I just clean them out now and again as they're not very high up and I put a "pop sock" or whatever they're called now(Knee high tights) over the end of the down pipe to cach pollen and small bits that blow off the trees. There's one hanging on the end of the rail having just been washed out. Works quite well. Last year I had quite a thick layer of yellow pollen on top of the water that went a bit yuck.
I have a basic composting toilet with a separate urine container which I have to remember to empty. If I was living further away I would have the urine going to a soakaway as it could get a bit unpleasant if the wee bucket got forgotten about for more than a day or two. The poop and sawdust bucket isn't a problem and sat half full all autumn and winter without any smell or fly problems. Might be different if the urine was going in the same bucket.
It all gets emptied into a container at the bottom of the beautifully manicured lawn. Its an old barrel with some holes drilled in, half filled with straw to help air circulation, covered with an old dustbin lid held down with a brick. I also add in coffee grounds and other kitchen waste and occasionally a bit of washing up water if it's all loking a bit dry. It's rotting down nicely. I keep a long handled brush near the bin to give the toilet bucket a scrub out after each empty.
One of the other hutters has been using compostable toilet liners and putting them in a normal metal dust bin with no extra holes and no straw in the bottom. I was not at all sure that that was going to do but I had a peek in it recently and it all seems to be breaking down nicely if a bit more slowly.
I have an Aladdin oil lamp which gives off an excellent light and a bit of heat which is handy on cooler evenings as I dont have a stove. I love it but it's a bit fiddly to opperateand takes a bit of getting used to so I'm not sure I'd be happy letting visitors use it and I'd be happier with a slightly sturdier table for it to sit on when grandchildren are crashing around. Otherwise I have candles in sturdy wide bottomed containers and a solar powered light for reading in bed at night so that I dont have to take anything with a flame near the bedding.
I was given the solar light by one of the other hutters who now has a much more sophisticated solar power set up in her hut. I also have a small solar powered radio sitting on the windowsill along with the little panel for the light
I also have an old filing cabinet for food, crockery and cutlery, hot water botles, t-towels etc which will hopefuly keep mice out but also keeps things quite cool. Not had any sign of mice in the hut yet.
I guess that if you have a stove then leaving the stove door open and baffles etc open when you are not there will give you some passive convection.
Given it is winter and warming cold air up leaves it very dry and inclined to dehumidify anyway it is a good time of year for you hut to dry itself when not used due to solar gain if you have a steady change over of air. I guess ti depends on your hut orientation and insulation level though.
If you have got the bulk of it dry and there is just a smaller bit o maintenance drying to do you might consider one or more of those chemical dehumidifer/moisture traps.
I believe they contain Calcium Chloride which can be got from ebay cheaper as refills if you shop around.
What most folk don't realize is that Calcium Chloride just absorbs water vapor and deliquesces anyway it is not a chemical reaction as such. So it is reversible and still works even when they look runny.
If you have what looks like a spent solution in a glass oven dish or some such you can dry it out again and go again when you light up your stove. It poses less of a disposal issue if you re-use it a lot.
I don't like the chemical moisture traps but have had to resort to them in places where leccy was not available.
Another option is a bucket of those silca gel balls again you can get the indicating variant off ebay that tells you when it needs drying. It can be used many times over. Just heat it up in an oven or on a stove top to dry it out and go again. The cheapest source of this stuff is to save up the bags of desiccant that get put in parcels etc.
I have used SIlica Gel to dry out the insides of boots and diving suits on may occasions (sown into a cloth bag). It is recycled and reused very easily with a careful application of the microwave oven. I also use silica gel with an electric heating element in a metal container in my 3D printing cabinet to keep the plastic filament dry. To recycle these I just put them in a draft (window crack ed open) and plug in the heating element.
The chemical method and the silica gel method though are no good if you have a lot of initial drying to do but will help you finish off and then maintain your hut when empty. If everything is as soggy as it sounds, the earlier advice from the other guys about airflow is the best option. Plus lots of stove running where you can..
I guess when stove drying out your hut then circulating the warm air is a good move too. There are those stove top peltier electric (heat powered fans) that may help.
Dunno if any of the above is any use but might be worth considering as options.