After completing above steps Should I also add 'grldr' and 'BOOT.INI' within 'E2B.vhd' ?
No, you should first test the image "as is".
Again what is the difficult part in repeating a given set of steps WITHOUT introducing variations of ANY kind?
Why you (but not only you rest assured ) are obsessed by (presumed) shortcuts and/or "easier/faster" ways to obtain a result?
Can/Should I not use 'WinNTSetu v.3.6.3' for creating VHD, Deploying WIM and adding VHD entry to BCD ?
Does the given set of instructions talk of WinNTSetup?
If they do, you use WinNTSetup, if they don't, you don't.
If the idea is FOLLOWING a given set of instructions, you JUST §@ç#ing FOLLOW them and not try each and every possible way to deviate from it, using other tools or other commands.
Completing the whole walkthrough exactly as is takes what, less than 30 minutes, why - just for a change - not trying to follow the instructions?
Does 'WinNTSetup v.3.6.3' not do exactly the same thing what we do with the help of cmd commands ?
Most probably it does the same exact thing , but you will never know until you make two images, one with the given set of instructions and one with WinNTSetup and you compare them finding which differences (if any) the two methods create.
BTW, you posted that you made a .vhdx (which is NOT a .vhd) using WinNTSetup.
If it wasn't clear enough , grub4dos will allow you access to the contents of a .vhd (and ONLY of a .vhd of "fixed" type) and NOT to those of a .vhdx,
I think think GUI is more simple and better than cmd commands ?
Most probably "simpler", hardly "better" (because you do not know what you - actually the tool - is really-really doing "under the hood".
Is it simpler and better to travel on a car driven by a chauffeur or to drive yourself the car?
It depends mainly on the scope, if it is to go from point A to point B, most people will like better having the chauffeur, but if the scope is to learn how to drive a car, not so much...