I think the game just requires knowing a ton, like most actual roguelikes. If you can get reasonably far in Nethack for example (make sure you use spoilers), Cataclysm should be doable. Even if not, just get used to pressing a ton of keys
On encumbrance, just drop your shit. They literally put in the feature so that if you drop a storage item, your inventory will drop with it. As for clothing, DON’T MELEE DANGEROUS GUYS WITHOUT ARMOR. Such a dumb thing to say, but really it’s a must.
If you don’t put points into skills, it’s a long start, and I’m talking like 10+ hours before you might get to “fun”, and then another 10+ to get to a secure point. I play long-term, and I normally have to spend the first year of game-time building survival, tailoring, some dodge and melee here or there, in between almost dying because of whatever. Almost dying being the key word there. If you have to set bushes on fire and burn down half a forest just so you can stay warm during the night after your arms were broken, so be it. Usually by the end of that year I have scavenged a library or a school, and grabbed a vehicle. By mid-year two is when I expect to be welding or getting into labs. The first summer is usually when I start hoarding food, if I can find a charcoal smoker. It’s easy to spend a ton of time in the dark crafting un-spoilable food, or building stupid stuff to raise skills.
I’d suggest smoker as a starting profession, you get a lighter and nice clothes. Immediately make balaclavas out of curtains, and wear an emergency blanket or two as long as you need.
Crowbar is usually a good melee, a two-by-four works. Anything with +1-+3 hit is the best. Melee is more important than guns, because you won’t level up your dodge the better you get with guns.
A nice thing is “tired” as I’ve played, is really not an issue. Even if your character is up for like 6-12hours after becoming tired, it usually doesn’t have a significant effect on skills, so it can be easy to rest your characters sleep that way.