Oops, I did not see your reply before I responded to myself!

I wonder if the heat spreader is needed when the 970 is in the bottom mount?

I replaced the mounting post on the MB with the medium short mounting post in the accessory bag and it worked as advertised. Do the latest version of the M.2 drives from Samsung use a thinner mounting board and that is the reason for the different posts?

The shortest mounting post that also came as a MB accessory must be for the M.2 mounting under the heat spreader? Since I'll probably never use that M.2 socket I did not remove the MB heat spreader to verify.

Again ROG/ASUS, it would be nice if there were some information on the heat spreader and mounting post(s) usage. But then that would take all the suspense and trial and error out of the installation.

Next question on installing and setting up the Samsung EVO 970 M.2 device - do I need to change anything in the BIOS?

I am running W10 with all the latest updates - 1809 edition. I installed the Samsung NVMe driver 3.0 and the Magician software version 5.3. All seems OK.

The BIOS (ver. 1003) has the following stuff under Advanced>Onboard Devices that appears to pertain to M.2 devices:
M.2_2 PCIe Bandwidth Configuration
PCIEX 16/8_1 Mode
PCIEX 4_3 Mode
M.2_1 Link Mode
M.2_2 Link Mode
All of these options are set to Auto. Do any of these need to be changed? Is there anything else I need to change in the BIOS?

Again, I could not find much on this subject for the Hero VII MB on "Google". Help appreciated.

I thought I was home free too. I installed the latest Samsung Driver and am running W10 1809 as I stated above somewhere in this thread.
Installed the EVO 970 in the lower slot.
Left all the BIOS settings on auto.
Installed the latest driver 3.0.
Installed Magician 5.3.
Had Windows Disk Management Initialize and format the drive.

All seemed OK. Until I noticed that the system Blue Screened each time it came out of sleep mode.
Installed the latest Nvidia driver.
Re-installed the latest AMD Chipset stuff.
Turned off Hibernate.
To no avail, the system blue screened and rebooted every time it exited sleep mode.

Removed the EVO 970 and deleted the driver and Magician software.
Problem went away. The system is now back to stable doing what it's supposed to do!

Can someone please tell me what I'm missing when I install the Samsung EVO 970 (512GB) device or at least point me to a detailed description on what I need to do to make this thing work properly. About the only thing I did not try was clearing the BIOS after the installation.

There you go! I really like talking to myself, I thought the ROG site had some experts to help guys like me. The link below is exactly the problem I'm experiencing. I made the "mistake" of updating to W10 version 1809 and as usual Microsoft threw a few glitches in the update.

https://answers.microsoft.com/en-us/windows/forum/all/internalpowererror-resuming-from-sleep-on-1809...

Anyway, I guess I'm out of luck using my EVO 970 until MSFT or Samsung gets around to resolving the Sleep/Wake issue.

Yes, I'm booting from a Sandisk Extreme Pro SSD. I did not want to jump in and clone the 970 until I was sure all was well.

Based on all the other guys with the same problem I don't think it's something I doing wrong. See Microsoft thread above.

But...are you using a AMD/Ryzen or Intel based system? What Motherboard are you using? If it is the Hero VII BIOS version 1003 and a Ryzen 2700X then we need to compare configurations and try to figure out what I and others are doing that causes the problem.

The Samsung Driver will show up under Controllers in the Device Manager.

Yes, you got me, I should have re-read the manual that came with the MB before commenting on the post size! That's the problem when you build a new system and then several months latter add a new onboard device. Common sense reigned and I figured out which post should be used - then I looked at the manual!

It's the Samsung's NVME driver issue with Windows about the wake up BSOD. There is a thread about it in Samsung forums with other users experiencing it as well and asking Samsung for an updated driver.