Hey Ken.
I like you wish that there was some type of way of knowing how far in the process the rendering takes or should take but alas not to be with this program I am afraid.

Maybe in the future releases.
Be patient and see what takes place. You mentioned two items I was immediately thinking could be affecting you in defragging and making sure nothing else is running in the background. I personally just let it run overnight and wake up in the morning hoping that I do not have a new coaster for my coffee.
Sounds like you are doing things correctly. What are your specs on your pc

: Maybe someone else may see something that will help you.
Hang in there.
Scooter