Okay, so most of this is probably irrelevant, but it sorta bothered me and then I /really/ got thinking...I'm fairly certain I know the DM's intent here, but it's still fun to play with.  <3

[hider=hypothetical stuff, don't read if you don't want picky questions]
It is a little odd that superstrength, magic effects, telepathy, and other abilities don't function on other characters/chars from worlds without such things.  I mean...I suppose it /might/ be to keep them from getting into nasty fights, but at the same time it feels odd.  For example: would a character with a gun be able to shoot a character from a world that hasn't created guns yet (setting aside the whole "don't use your weapons, kids" thing for the moment).  What about if technology degrades in char B's world, can char A's digital camera take a picture of them?  If a char can lift a rock the weight of another person with ease, why can't they lift the other person with that same ease?  (It's possible that your example implied that Carter could, but I'm not /entirely/ sure.  Clarification would be appreciated.)  Any species that uses some sort of additional sense -- say telepathy -- would be very thrown when they can't sense the minds of anyone else.  And a species that relies upon, say, spatial awareness instead of vision would by this logic be completely unable to know where anyone is.  So if I had brought Cecilly, she'd be truly blind in regards to other characters, instead of merely technically blind.  Her eyes do not work, but she has an ability that lets her detect locations of things.  It still interferes with other aspects of life, like reading, and any sort of long distance "sight" is right out.  If char A the mage creates a fireball and throws it at char B from a world of no magic, is it just fire, and so would it burn?  I mean, a fireball created normally would burn, so what if they literally /make/ a fireball, instead of just casting it as a spell?  Or is it still magic, and so it would do nothing?  How about a spear made of summoned ice?  These are primarily combat examples, but there's other ways to employ them.  Say, using Feather Fall or Fly on someone about to plummet to their doom, or creating an ice ramp from nothing.  Can the mage chef feed others with food created from thin air?  At what point does something cease being "other" and become properly tangible?

OH.  Actually, to take this a step further, if there /is/ a species without any vision, does that mean vision ceases to work for all the other characters?  I mean, the assumption that vision is standard is a human-centric version.  Or, say, a species with very weak physical abilities -- would they suddenly be able to throw a human where before they could not, simply because if they were human they'd be able to?

...not that this affects Alys much, since she's functionally vanilla human, with a very few exceptions.[/hider]

tl;dr half-coherent Shy thinks too much.  Working on a sheet right now.  ^.^