Nope, a CMS has nothing to do with seo, Setting the CMS up CORRECTLY is the key ;-) Clean urls, title tags, meta descriptions non dynamic etc , Hope that helps.
I don't think it will affect to SEO. Today many sites are developed in various CMS systems but they also rank well and well optimized.
If you know your away around CMS software, you can optimize the sites very well. Many CMS are not too SEO friendly coming out of the box. You need to learn how to use the SEO features or use additional plugins. The key is to have a handle on CMS first, then figure out the ins and outs of the SEO for your site.
It depends... The CMS itself neither helps nor hurts your SEO. How you implement your site using that CMS is what can help or hurt you. In other words, how your templates or themes are written will generally determine whether implementing your site with a CMS was a good idea or not from an SEO perspective.
Well, I personally think that CMS only plays its role in SEO when it comes to optimization. I mean, you can optimize CMS based websites pretty well. And that's why it plays a vital part in your search engine optimization. Enjoy...