Open EM Client email / assign categories

Have been trying EMC for a couple of weeks and am beginning to like it more than Outlook.  But, I still have a few easy questions.  Here are two more. 
I have set up a rule assigning a category to an email.  When they get to my email page, those emails are black - not the color I assigned.  How do I get the EMC rule to assign a category/color to an email?
I can’t seem to highlight an email and open it with ENTER or a double click mouse click.  Only way to open it is Right Click>Open.  Is that the only way to open email?