Keyboard key reassignment

[Jester]

I purchased one of these:  https://www.ebay.com/itm/FANTECH-FTK-801-USB-Numeric-Keypad-with-23-Keys-4-Office-Hotkeys-for-PC-Laptop-/282152972047

I was intending to reassign two of the upper keys to: G and SPACE.

I tried using "KeyTweak" to do this. Looks like Win7 intervenes somehow, I can reassign any of the other keys but not the Windows specific buttons (that I don't want or need). Looks like KeyTweak  over-writes something in the Windows registry and I guess MS does allow this for other keys but not windows specific keys.

Does anyone know of a work around or have a link to a dirt cheap numeric keypad with generic or re-programmable extra buttons?