I am just beginning my wiki and could use a little help.

1.  How can I change the web address tab to my company domain?
2.  How can I change mywikkasite to my domain name?
3.  I was able to create one new page by watching video and now cannot create another by clicking in comment box.  When I press edit it takes me back tot he page I was just on.  I cannot decipher how to create a new page as an action.
4. I downloaded the html for my font colour and put it in between the quotes for colour.  The message I kept getting was that I had not chosen a highlight colour.  Is ther another code for colours?
5.  How do I set up user permissions?  I want only members of another site to be able to add content.

I chose Wikkawiki after comparing because is it was easy to upload, offered user permissions and seemed simple.  My concern is that if I can't make simple additions, this whole project will become a heavy customer support headache.  The point is to make the system accessible to lay people isn't it?  Is there another wiki that would be a little more newcomer friendly?  I don't mean to by your customer service headache!