I'm a little rusty with the game, but I remember some details and options for trouble shooting when applicable.
1: I don't recall ever finding how to get more feed for mushrooms and worms, which I did find annoying at first. They are more of a temp food source iirc from what I was told in the past. Try to minimize harvesting them (the more there is, the more it grows, or something like that), and focus on plants and fish as soon as possible for food.
2: I don't understand how this is an issue. It is Emergency Life Support. You don't really need it if you are 'outside' of the base. It is for when you are 'in' the base, when the atmospheric conditions are bad for some reason. I personally don't recall it ever having external access, and it is not exactly setup to double as an airlock. There never was a reason I found to need to access it from the outside.
3: I never noticed that myself. Not sure how I missed that myself (I have dozens of hours in the game...)
4:
Where is the ore from?
Same ore from same drill site?
Same type of ore from different drill site?
Different ore from different drill site?
Has a power shortage at any point caused it to power shut down at any point?
It's been a while since I played, but have you removed the elements created from the previous batch of processed ore (I forget how the processor handles it, its been over a year at least)
So many issues? I've had this game some time, although it has been a while since I played (RL stuff...). I've dealt with far worse. Like stuff vanishing, equipment stuck in the rovers, being 'stuck' on a repair mini-game, taking damage while just walking around in the base...
Also, development on the next game/version/sequel is in progress, so it is unlikely MC:C might not get any more serious bug fixing done unless it is some easy to track and fix issue. Like 3. But that's not exactly a game breaking bug.
On a side note, we are not dealing with a AAA Dev. It's not like there is an army of over paid, over worked programmers sitting around being ordered to ignore bug fixing to focus on other money making projects instead.