I'm sorry I just can't figure out, how to install the August Update.
The May Update no problems to install.
Every Time I use your method above I'm stuck in a Boot Loop.
You are not alone friend.
I was able to flash the update once, but it didn't take and just powered off the phone every few minutes at random. Was completely unusable for me.
Note of caution, somehow in all the flashing of different things I managed to wipe/corrupt my EFS/Persist partitions, which has now led to major issues with 4G and Wifi on my device (shutting off and on every 30 seconds or so). Learn from my own idiocy and make sure to take a back up of the efs and persist partitions and save it OFF the device. Will save a lot of headaches in case something bad happens (as it did for me).