I'm glad now we are talking about support, so sad I had to react like that in order to get help.
I don't expect anyone to do the job for me, but maybe correct me if I'm doing something wrong.
I replaced the code like I said (I have a custom field named cb_class already created in the backend, now I edited the file like said previously)
and I get this:
I think I'm missing something, like I have to declare some variable in php, or use another snippet to get that field from db, I'm stuck with that.