Sophos is actually one of the top corporate anti-malware/anti-spyware/anti-virus platforms.
They have a home version as well which is centrally managed through your home account web interface.
Basically once set up, can prevent users (my kids) from changing settings or disabling of the protection.
Installed Win 10 Pro per the online license associated with the laptop, then purchased upgrade to Workstation for the Storage Space management and ReFS.
Z: is a NAS drive where downloads are stored. Not sure why that would a bit of difference, but could try it just for kicks.
Note: Downloads folder would have nothing to do with booting from ISO hanging.
Spoke with ASUS support to try and get started working with their engineering support to try and determine the root cause for this platform issue so that when 11 is released Oct 5th, they won't get a black eye for having a bollixed platform.