First off, when you say “I’m not using WASD, and understood how much it hurts to not play on your desired keys and unable to reassign them.” I am assuming this is in game controls, not editor controls. These can be manually remapped under Input in Project Settings; however, you cannot change this during runtime, without the plugin, which I will now explain.
I am going to assume you are using UMG from your menu, what you’re going to want to do is, create a button that when clicked on, creates the widget Main by, this is all you need to do, the plugin will do the rest; however, you must first have added Inputs under Projects Settings, or nothing will show up. You will also need to add a button to remove or collapse the widget, it should save the bindings by itself.
There is currently no way to rebind Inputs in blueprints 
you must use programming, or’s Plugin. You do not need’s Engine, it comes with a lot of extra stuff, like custom functions and macros. As for the Engine version not being compatible, is that for the VictoryEngine or the Plugin, and are you using Unreal Version 4.11? (That just came out, so most likely has not updated the Plugin or the Enigne) You will need to use an older version of Unreal, or wait for to update. If you are already extensively using 4.11, I can tell to update the plugin, but I don’t know how fast he will be able doing that, since he is quite busy :).
If you need more help on how to use the plugin, just ask and I shall make a more detailed explanation!