The One Who Connects

Most relevant WoBs I could find. (1, 2, 3, 4)
We've also discussed some of the topic in multiple threads in the past(with inconsistent results):
As it turns out, there's a lot that we don't know.
I do remember speculation on here that intent has a little to do with that. (this explanation is gonna be a little wonky, fair warning)
We were thinking that you wouldn't go "off-world" without intending too, so the local CR is functionally a globe if you are just using the CR to travel around the world faster. If you jumped into the CR in say.. Jah Keved, then Alethkar is gonna be to the east. If you intended to use the CR to quick travel around Roshar, then you could continue east a little ways past Alethkar/Shattered Plains and end up in Aimia, something that could only be done on a spherical plane. But if you intended to worldhop towards Scadrial, then you could walk past Alethkar and into the darkness between planets, something that can only be done on a flat plane. This duality is made possible by the fact that the CR is literally shaped by perception.
To use a potentially clearer example: the Columbus story. He felt that he could get to India from Europe by sailing westward around the world. If he had went into a Cognitive Realm for Earth, he would be able to do just that(after crossing over the Americas, of course). But if someone intended to go westward and fall off of the planet, they could reach the "edge" and go into the darkness between worlds before they even crossed the Atlantic. What this means for when there are multiple people is unknown, and is yet another thing that is breaking our brains.

We have the problem that we have all sorts of information in all sorts of places. Arcanum was meant to condense everything into a singular location, but as Pagerunner mentions, that takes time. In the meanwhile, have my shortcut:
We have a few different WoBs that say some related things:
Plus a little speculation:

I think the answer is yes. And I think the reason normal Spren don't escape but an Unmade might has to do with Sentience. (I have no evidence for that yet, but it makes sense)
Bigger Gems can hold more Stormlight. It stands to reason that a bigger Gem could hold a bigger Spren.
It doesn't actually say that. Per the Notebook:
The Cognitive Realm of Sel(which is 1.5 times as big as Earth) isn't big enough to contain two Shards. Half of that(b/c 2 Shards) is 0.75 times the size of Earth. I don't think they have any Gems lying around big enough to contain that much power.
As such, I'm gonna say it's not feasible. (I am not saying such an action is not possible though. Be aware of that distinction)

Well, our Golden-haired Iri are 3 planets removed from Roshar, so H&C probably didn't do that.
Doesn't get us any closer to knowing who did, but ruling out possibilities is good.

Adonalsium may have created Yolen and all the people on it, but I don't think he directly created Hoid's generation of people.
Adonalsium created several planets, including but not limited to Roshar. Yolen and Nalthis had humans on them pre-shattering. While Adonalsium was doing that, I think Yolen and the people on it existed for quite a while before Hoid and the Vessels were actually born. So I guess it would be a question of semantics: Ruin and Preservation created the first people on Scadrial, but does that mean that they "created" the current generation? The same applies here.
In Books 1 and 2.. I don't believe so. We have a WoB that we will know what the Sphere is by the end of Book 3, so there's that.
Nohadon mentions Surgebinders. Surgebinders came into existence because Spren tried to imitate the Heralds. At the absolute earliest, Nohadon was alive for the Second Desolation. The Heralds fought off the First Desolation, which would've been a minimum of about 350 years prior(by my estimates). So the Heralds predate Nohadon by at least 3 centuries, possibly more if he was in a later Desolation.
Nope. The only things that are canon about him are written on that page of the book. Brandon has given us nothing more, nothing less.

Sure. It's come up from multiple people across multiple threads, so there's some new info for me too.
A Line from the Kaza Interlude that started the discussion.
From Blightsong back in May(after the Kaza Interlude was read at a signing)
From Kimni back in August.
From Calderis in September.

Basically, Brandon has always referred to him in some manner of "the man who calls himself Taln" and the community is divided on the truth of the matter.
I think he really is, some people think he isn't, others think that he was, etc.. ask six people, you'll probably get four different answers

It's Canon actually, but it's close enough
It's Shadows of Self(SoS) [...] The Lost Metal is gonna be a lot sooner than ten years, You had me worried for a second there
To @Lord Maelstrom: I have a few suggestions you can use to catch up on information.
Ask Questions: All of us remember info that others don't know off-hand or forget things from time to time, so questions are always welcome. The Coppermind: Wiki of all things Sanderson, and although some articles are a bit out of date because of the wealth of recent signings, most everything is sufficient enough to give the basics The Events and Signings Subforum: Counter-intuitive as it may sound, it's a good place to learn new things. Every answer is straight from Brandon, accurate and verbatim. And since most of the discussions there try to find new meanings, you have explanations and interpretations already written down for you. All else fails, read a few theories: You aren't the only one who is new/confused about things, so someone may have probably asked the thing you were wondering about and got an answer. if they haven't, then do the asking yourself. If you can deal with the wounded pride about being wrong, post a theory about something related to your limited knowledge. You'll get flooded with corrections, most of which will give you new information that you didn't have before.

It has been assumed (not directly confirmed iirc) that all of the compounding powers have limits that you can't cross. Steel Compounding is limited by air resistance for example.
I figured that double pewter couldn't go further than the Koloss go, for the same reason that they cannot keep going. Outside of organ capacity and bone structure, you have to consider the expansion of skin that the Koloss go through when they increase in size. Gold compounding would keep you alive, but I agree with Itchy, it might try to revert you to normal.
All that having been said, you wouldn't try to discover the limit unless you had to. You would store 90 and some odd percent of that compounded strength to use for later.

We don't know for sure.
As for the Honorblades, many have speculated that they are Honor's equivalent of Godmetals like Atium/Lerasium. I haven't managed to find a confirmation, but I have not checked recently