There is a setting which makes the highlighter think ’ is dialog, you have to change it to " otherwise it jumps in and out of dialog like this every time you write something like I’ll or it’s. The same goes if you forget closing the dialog with a " at the end, then it keeps making everything dialog (which is shown as the pale, grey cursive)
EDIT; Now I am the computer and could look it up.
You want the “Language” menu, and you should choose “choicescript” from the drop down menu (it starts at “user defined”.
Once that has opened, go to the “Operators & delimiters” tab.
Now, if I remember correctly, in one of the “delimiter styles” you have ’ in the open and close boxes. Remove that, or replace it with ". Once you save, everything should look peachy.