Is there a penalty in MSN/LIVE if you have multi-URL's that point to 1 website. Could be 100 URL links pointing to 1 website.
100 url's pointing to one page ? that's not a very bright idea. Jus use a "this page has been moved" page instead unless you are really looking ot jump into cloaking business, which I think you should not
Maybe, if you do it right. This article has a couple paragraphs specifically addressing multiple domains and the duplicate content penalty: http://searchengineoptimism.com/SEO_Tutorial/google-duplicate-content.html
Could you explain what you mean please? That just sounds like you have a lot of backlinks, unless I'm misunderstanding what you're saying.
That's extremely good for SEO! Try to get as many URLs pointing to that site and it will rank or at least get a good PR.