I was just wondering, if i have a 1/1 character at the battle, and my opponent gives him -2/-2 hes now a 0/0. if i give him +1/+1 hes still a 0 as far as i know because the negatives are accumulative though he cannot contribute a negative value to my knowledge. So if i leave him at a -1/-1 and i control the favor would my skill count be 0 or 1?

after reading more, id think that since it says my guy cannot display negative values, the favor would give me the 1 force to claim a ring. Am i correct in my findings?

Yes, as long as you have presence there.

Yes. Modifiers played on/targeting a character apply directly to the character's skill value(s). The Imperial Favor is a separate bonus to the total skill value for the conflict, so it isn't calculated into the running total of modifiers on any of the characters (which is also why it still counts even if all the characters on that player's side of the conflict are bowed).