By the way, I used the MS supplied creation scripts (Install-SharePoint, New-SharePointFarm) on my first WFE. I used Join-SharePointFarm on my second WFE.
I added the property on the first WFE by using -
$ver = "$($(Get-SPFarm).BuildVersion.Major).0.0.$($(Get-SPFarm).BuildVersion.Build)"
New-ItemProperty -path 'HKLM:\SOFTWARE\Microsoft\Shared Tools\Web Server Extensions\14.0' -Name Version -Value $ver
When I went to do the same thing on the second WFE, it told me it existed.