[Aliens]"...solitary giant predator caterpillars. Civilization wasn't easy for us"

[Dinadon]

Right, let's start with some things from your first post.

Originally Posted by vicky_molokh

Trophic Level and Strategy: They're canonically carnivorous, compared to the Hawaiian carnivore caterpillars in this aspect (I assume that means 'refuses to eat foliage even if starving'). Again, their manner of hanging on to something seems like a hint towards Trapper or at least Pouncer. Trapper also seems to fit well with their territoriality. Hijacker is likely an occasional alternative, but definitely not the primary, given the mention of even larger/stronger lifeforms. They get Restricted Diet, right?

I'm inclined to go with no, if only because I can't find an animal template with it on that isn't mythological. I'm also fairly certain cat and dog kibble isn't fresh meat, despite both being carnivores. Anyway, it sounds more like they won't eat plants, not can't so it seems a little moot.

Number of limbs: 4 arms on the front-most segment (there seems to be some claim that 2 of them are occasionally used as supports, not manipulators); 4 legs (maybe more - it is not quite clear) on the rear-most segment. Gets a bit complicated by not having much more than a portrait in the official sources. Should this reduce Control Room Multitasking Penalties?

Only if their minds are capable of it. Just because you can coordinate lots of limbs doesn't mean you think about two things at once. It's the latter that I feel is more important inside a control room.

So, Spawning is right out. Live-bearing or egg-laying both seem reasonable. Are there objective reasons why we might exclude or prefer one of the two?

I wouldn't say spawning is right out. If the young aren't seen as food or interlopers, then it's possible for them to hang around an adult.

As for eggs vs live, being pregnant isn't easy on the mother and makes it vulnerable. Eggs simply mean that there is a location the mother protects, the mother herself isn't really weakened for any significant length of time.

Strategy: As I mentioned above, a strong or moderate K-strategy seems to be implied. While completely not grounded in canon, I'm considering the idea of always having 2 children, one left with the male, one with the female (the race doesn't seem to have a concept of pair-bonding).

Bears are solitary, K-strategy and don't form pair-bonding. The mother raises the cubs on her own. Solitary big cats are probably another good place to look.

Vision: being carnivorous climbers is an incentive for good vision; Normal Vision seems the most obvious choice. They have eyelids of some sort, but given their pictures, it is unclear if they have faceted eyes and/or nictitating membranes over their eyes - they don't look like they have the human differentiation between pupil/iris/white. It is unclear if them being predators predisposes them to Infravision. Right now I'm about to leave them with Normal Vision, but what are the possible reasons for having either of the two options, and the consequences faceted (insectoid) eyes for large creatures?

A faceted eye gives you more receptors, letting you notice small changes easily. Some form of Enhanced Time Sense might be plausible at the extreme. Acute Vision would be the minimum. If these are like insect eyes, Ultravision might be appropriate as I think insects can see further at that end. Realistic Infravision requires dedicated senses for the task, but targets that can be picked out from the background temperature is an important necessity.

I don't know enough about insect eyes to know how they respond to damage, poking them in the eye may knock out the facets you poked, making them harder to blind that way.