Typically, I would just translate it to, "you are bad", "you're a bad influence". When somebody is 有毒, it means that it is bad to be around that person, or something bad might happen when you're with that person. It cannot be used as a complement, UNLESS you're being ironic, say it jokingly, or something.

1. Someone has bad luck, or brings bad luck to his friends, means 他有毒. 2. Someone play tricks on his friends, just like poison his friends, also means 他有毒.

This is my favorite ahh You can say this in a kind way with your friends You can also use this term show your angry Kind of like " what's wrong with you?"

It's a garbage. Forgot it.

perfect question. As a Chinese native speaker, I actually don't know how to accurately answer your this question. But you should know that the meaning of this word "有毒“, in your examples, is not poisonous. There are different meanings in different contexts. In general, "有毒” can describe a person who performs well or badly. And remember, the two Chinese characters should be used together(有毒）. BTW, This is an informal way of oral speaking. May my description can help you have a better understanding.☺