Yesterday, after reporting on my two online applications and one telephone application progress, I decided to try another online application and also printed out a paper application (thanks to agkhalil123).
I discovered something that is not mentioned on the healthcare.gov website - sometimes the format of your answers is not accepted, but you wouldn't know unless you guessed and changed it. It asked me how many hours a week I work. I work 37.75 hours per week. When I changed that to a whole number, voila! - I was able to move past that section and get to the next part which again told me the system was temporarily down and to try again in 30 minutes.
So, now I'm not sure how many of the blank pages encountered are due to unaccepted responses. On my other online applications I am unable to go back and edit my applications, which is why I start new ones.
In the end, only one will be put through and confirmed with my sign-off. I may be creating several applications, but none of them have allowed me to enroll and confirm. I will only do that once.