Yes, I have the same confusion.
Actually, start_vm = "no" will not shut VM down at this time in env_process.py.
I am doing some work to introduce a param named vm_status = [shutdown| running|paused]
I will keep the start_vm and paused_after_start working also for old config file.

There are some situations:
(1) no vm_status configed: start_vm and paused_after_start work.
(2) vm_status exists and some confliction with start_vm or paused_after_start_work:
                   the final desicion is by vm_status.

What do you think about ?