No, editing a message does not count as a contribution. Writing a message, however, counts as 1 contribution.
Yes
Yes, it counts as a contribution point.
Message Boards and Question Discussions both count as community contribution points on WikiAnswers.
Currently, the Community Forum does not give any contribution points; it does not show on your contributions page. However, posting a message on a message board does count as a contribution and does show on your contributions page.
Technically, it is called recategorizing, and does not count as editing. Although you are 'editing' categories, it doesn't count as editing.
Editing a profile counts as a contribution to Community. You can check this out by looking at the Stats box on the right-hand side of your profile, and letting your mouse hover over "Community." (See Related question below)
No, it does not count as an organization contribution. I counts as an 'Edit' contribution.
Quality contributions include asking, answering, editing and recategorizing questions. Community (message board) contributions do NOT count.
No, you do not.
Giving a Trust Point does not make any significant contribution to the site, as giving an answer or editing a question does. If that were the case, members could easily give out Trust Points to gain contribution points, which defeats the whole object.
It does not count as a contribution because you are not changing the WikiAnswers database by hitting the button. If you were to remove this harmful answer or to change this question to be appropriate, then it would count as a contribution.
How to develop the message