Cat questions for cat experts?

I'm no expert but I have owned cats all my life and I can tell you every cat is different with a different personality. I have a Manx who I'm told cries all day when I leave for work and locked in my room. Then someone opens the door, she goes out, then right back in the room where she stays until I get home. Every day when I come home my cat goes to the scratching post, even though it is there all day. As long as the cat is healthy and happy don't worry. As for the biting, make a loud noise or yell at her when she bites. I have my cat trained so well she is like a kid. She can tell the difference in the tone of my voice and she knows when she's in trouble. Also, if she is doing something bad, I clap my hands loud and she stops.