Jishoku has negative means. It means '' take a responsibility of work ''.
On the other hand, Taishoku has positive means. When you will retire or change your job, you should use ''Taishoku''.
I think Kyuujyo and Kyuushutsu, Kyuuen are almost same...
When someone is drowed at the sea, you will help him. This is "Kyuujyo''.
When someone is to be left behind fire, you will help him. This is "Kyuushutsu".
When big earthquake occurs in somewhere, you will go there in order to help victims. This is "Kyuunan".
"Souzou" is "create" or "originate".
These are my opinion. So you may have to hear the other opinion.