殊: Why 歺(歹)+朱? How did it get to mean special (in a good way)?
I haven't found any reference on it, so I come out with my own ideas. 

Phonetic loan. In the beginning the ancestors created the character 殊, but the same sound also means "special" to them. The ancestors are as lazy as us, so instead of creating a new character, they borrowed the character 殊 to fill the blank. This is not as likely as my next speculation. 

Amelioration, a form of semantic change in which a word's meaning is changed from bad to good:


Originally 殊 means to put to death, which is an extreme measure, hence very and overly. 
殊 puts life to death, hence different.
If it gets to "very" and "different", there is no way to prevent it to mean special.


This, I think, is probably the case. For comparison, the English word dead could also mean very, completely, or exactly, all positive meanings.