Applied the fixes and also changed the resolution to 4k.
Still at full screen mode, it's running at 25fps, but seems to be working okay with windows mode. Menu has some flickering issues, but so far so good.
Found another work around (found via Steam Community) to fix that full screen 25fps issue... I can run external program called ForceFix in the background - and now the game play at 4k full screen is pretty much locked at 60fps. But somehow, the cut scenes are like 80-90fps for whatever reason.
Never knew about PCGamingWiki - but thanks to you all, found a good site.
All the installation guide seemed overwhelming, but once I just sat down and start reading how to do it, it made sense!
(Got my ass handed to that red-sword samurai on top of the train. It's my first playing, and oh boy. MGR is like Ninja Gaiden on offensive overdrive! Just how like it. Wish there was some z-lock feature for 1 on 1 fighting, unless I'm mistaken...)