1. Check the roots, as mentioned. Heavy root damage can force the leaves to drop.
2. Remove the spike with a sterilized pair of cutters. The plant is wasting precious energy it could use for recovery by using that energy for reproduction.
3. Please post a pic so we can see what's going on. A post with a pic will get a far faster and more accurate response to the problem than a post that's asking how to solve a problem but it doesn't have a photo.
4. It is crown rot. But crown rot is usually not a cause of the problem, it is usually a symptom of the cause to the problem.
5. Yes, a leafless Phal is still alive as long as it has enough living/healthy roots to support a little piece of tissue in the center of the root mass called a meristem.
6. Please read the sticky:
http://www.orchidboard.com/community...ends-here.html from the very beginning.
7. Sorry to break it to you, but I'd rather tell you the truth about this instead of having you believe in something that's not true at all...
There is currently no known Phalaenopsis that is naturally true blue. The flowers are the result of people dying them blue.