Here's an update on downloading the Windows 8.1 Pro ISO 32-bit using a Windows 7 VMWare Player Virtual machine from Microsoft. It works without any problems. Your speeds will depend on your PC capabilities and Broadband speed - I have a pretty slow laptop, but reasonable broadband speeds typically 20-40Mbps over WiFi
I had already upgraded from 8 Pro to Windows 8.1 Pro via the Windows Store update, and there seemed to be no way to download the ISO under Win8.1 using the various methods described elsewhere on this Forum.
I downloaded VMWare player
Player Version History | United States and installed it on Windows 8 -there are excellent tutorials available:
Windows 8 Tutorials[2]=Virtualization
I mentioned in a post above that there are Microsoft VMs available from
Cross-browser testing simplified | Testing made easier in Internet Explorer | modern.IE . I selected Windows as the desired testing OS, and VMWare as the virtualization platform, and IE8 Windows 7 as the 32-bit VM. (Annoyingly, there is no indication whether the VM will be 32- or 64-bit, except the size of the total download - bigger downloads are likely to be 64-bit, I guess.)
I downloaded IE8.Win7.For.WindowsVMWare.parts 1-4 VMWare WinRar executable. Takes about an hour to download and expand the archives, initialize the VM and update the VMTools on VMWare Player.
This Win7 VM is 32-bit, but it is an Enterprise version. (I will check later to see if there is a 64-bit version. The procedure for downloading a 64-bit ISO for Windows 8.1 will be identical to the 32-bit method, but times and filesizes will differ) Pro or Core versions will depend on the product key you have for Windows 8 - the ISOs contain a single image only. You will not download an Enterprise version here.
On the new VM, I downloaded Firefox beta and Chrome Canary Build, because I did not want to risk using IE8, without greater antivirus or malware protection. I did not want to go the whole route of setting up MSE and all the endless round of Windows and Microsoft updates on the VM that entails.
In the Win7 VM I went to
Upgrade Windows with only a product key - Microsoft Windows Help
First tapped Install Windows 8, to download and run Windows8-Setup.exe. It asked for my Win8 upgrade key, and accepted it, and started the OS download. It was faster in the VM than using an installed Win7 - I had downloaded 3% before I managed to quit the setup!
This initializes files in the C:\Users\IEUser\AppData\Local\Microsoft\WebSetup folder which are used by the Windows 8.1 to validate the Windows 8 product key you have supplied as if it were a valid Windows 8.1 product key.
I then tapped install Windows 8.1, downloaded and ran WindowsSetupBox.exe It also ran faster in the VM than in 64-bit Windows 7 home. It started at the estimating time and completed the download in about 12 minutes. Here are some landmarks in the websetup folders:
BIT39C0.tmp 8.34am 2048012 KB > WinPayload.esd 8.46.amm 2048012 KB > 3 more minutes to check the download >
WinPayload.esd.decrypt 8.49pm 2048012 KB > getting files ready as c:\ESD was unpacked (date of modification 9/30/2013 5:40 AM) > c:\ESD\Windows\Sources\Install.esd 9.06am 2031695 KB > select ISO image as media to save to >
c:\users\IEUser\Documents\Windows.iso 9.10am 2544768 KB
36 minutes start to finish.
Burn image to DVD if required (I did not do this) - I would not do this within the VM - I would transfer the ISO to my main system across the Virtual network and burn from there.