Here are the answers to your other questions, CP. Please note that these are the official answers from the DMs of Ysgard, and as such are not to be argued. Also note that these answers are for Ysgard ONLY. Arkaz will be posting their own response.
Q. How reliably does the amount of inventory space an item requires correlate with actual size of the item?
A. It doesn't. A gem (unless it's the fabled Eye of Argon) does not actually take up the same amount of space as a gem pouch, to cite just one obvious example.
Q. How well can a character determine weight of items without a scale available?
A. This depends on how good the character's player thinks the character honestly is at estimating the weights of things without using a scale.
Q. When characters travel between worlds, do they have any automatic sense of local differences? Or, do they "feel the same as always," barring specific events?
A. It is customary for characters to react accordingly if they go into an area and there is an environment messsage that says something like: “You feel uneasy here, as if you're being watched.” In the absence of such messages, most people do not RP any differences, although if they have strong IC reasons to, they might.
Q. I've been generally acting on the idea that characters know what their own abilities do. Is this accurate?
A. It is not unreasonable to assume you know what your abilities do, and it is also fine to roleplay that you do not know, and are learning them as you go along. It depends on the nature of the abilities and the path that has been taken to learn them.
Q. How much information does a successful identification of a spell/power entitle a character to?
A. You may roleplay this as you wish, bearing in mind that your roleplay should always be based on your character's actual experience with the spell in question. Good players sometimes ignore good spellcraft rolls if it doesn't make sense ICly for their character to know something.
Q. How much do characters know about the effects of their own spells/powers and such? If a character tried to cast "Charm Person or Animal", would he know if the spell worked? If he realized it failed, how much could he know about why?
A. You may roleplay this as you wish, again bearing in mind that your roleplay should always be based on your character's actual experience. The engine tells you whether or not your spell worked. You can know that if you wish, or you can decide not to have your character realize that. You are likewise free to speculate as to why the spell did not work, but your speculations may or may not be correct.
Q. Can a character distinguish different levels of potency (i.e. +3 vs. +7) in spells he casts on himself?
A. Yes, although obviously characters should not use the terms +3 or +7. It is established practice to use instead such terms as “7 runes of power" or "3 runes of health" (for a +3 con).
Q If a character has harmful effects on himself, can he tell, and can he diagnose himself correctly?
(Also, can he diagnose others?)
A. You are free to roleplay this as you wish, again using as a guide how much experience your character has had with the harmful effect in question. A character cannot, obviously, diagnose someone else unless they can see or are told the other character's symptoms.
Q. Are spell levels actually supposed to be IC concepts?
A. Not as such, but referring to spell “Circles” is established practice.
Q. Are Psionic Power Points an IC concept?
Q. How aware are psions of their reserves, and of the energy required for specific powers?
A. Individual Psions may roleplay this however they choose.
Q. Are item/creature/object descriptions IC info or not?
A. It depends. Please refer to the guidance you have already received on this matter.
Q. Is the “Hostile” status IC info?
A. The “Hostile” status is only IC information to a limited degree. Characters have no idea that other characters have them set to hostile, and of course have no knowledge that the hostile status exists, because for them it does not. Characters do, however, know that a character in their presence who has them set to hostile does not like them.
Q. Is it reasonable for a character to believe that a spell such as “Call Lightning” (or any other effects that target enemies) would strike all hostile status creatures?
A. It is unlikely that a character would believe such a thing, given that characters have no knowledge of game mechanics.
Q. What does the color of a floaty name mean, ICly?
A. Floaty names are OOC information.
Q. If one PC sets another to hostile, does that do the job for both?
13thHour : [Tell] *your alignment has long since passed any possible further move to 'sexy' due to reinventing the scale*
Lexy on the Wiki!