OK, you can still do it this way.
This will end up with Windows RT 8.1 Update 3 installed
All you need is a good 4GB USB memory stick. Backup anything you want to save from the RT to a PC, another memory stick or the micro SD card if you have one installed on the RT.
Download the Windows RT recovery image
https://www.microsoft.com/surface/en-us/support/warranty-service-and-recovery/downloadablerecoveryimage
SurfaceRT_BMR_10.8.17.0.zip 3.033GB
Extract the zip and
paste all of the folders and files in the
SurfaceRT_BMR folder to the USB stick. There is enough room on the drive to create a MSU folder for the downloaded msu files.
Restore your Surface RT with the recovery image booting from the USB drive.
Put the RT on the charger. This is going to take several hours to complete.
Turn the RT off and boot from the USB drive, press and hold the volume-down button while you press and release the power button. When the Surface logo appears, release the volume-down button. It will take a while to boot, maybe a minute or longer.
You will have the selection, - ‘Just remove my files’ or ‘Fully clean the drive’. Select ‘Just remove my files’. Fully clean the drive takes hours.
One of the pages will ask for a drive encryption key. Go to the bottom of the page and
select ‘Not this Drive”
When the reset finishes, in settings go to ‘Power and Sleep’, ‘When plugged in’ set to ‘Never’
All updating is done from the Control Panel, Windows Update.
After each search for updates is complete click on the blue line that says ‘important updates are available’ to see what is found. You can speed things up by hiding all Office updates. Right click an Office update and select ‘Hide’.
Install all other updates found.
When Windows updates are all done and Update 3 is installed go back and restore hidden updates and install the Office Updates.
Start Update Instillation Here Following the reset
Turn on WiFi, Search for updates from the Control Panel, you will see a firmware update, install all Windows updates, restart
When you go back to Windows Update it will show updates are available. Do not install these updates. What you need is KB2919355 and it will not be there. Stay on the page and search for updates.
Install KB2919355 along with the other updates. Restart.
Go to Control Panel, Programs and Features, View installed updates. See that KB2919355 is installed.
Turn off Wifi, install KB3173424, restart
Install KB3172614, restart
Turn on Wifi, search for updates, should find over 200 updates, install, restart
Turn off Wi-Fi and install KB3097667
After the restart, right-click on Taskbar > Properties, Start Menu. Check the box, Use the Start Menu instead of the Start Screen for no more metro screen.
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KB3173424, KB3172614 and KB3097667 are standalone MSU update installer files that you download to install at the correct time.
Download KB3173424 HERE.
Download KB3172614 HERE.
Download KB3097667 Windows RT 8.1 Update 3 Standalone Package
You can download these ahead of time and place them on a USB drive to install at the correct time.
Your steps do not resolve the issue. The black login screen comes up right after installing
KB3097667.
I NEVER had this black screen issue before. Something changed.