Unverified. All codes are used by holding R-SHIFT (right shift), tapping via arrow keys, and release R-SHIFT to complete input.

Invulnerability toggle ... hold R-SHIFT, input RIGHT, LEFT, RIGHT, LEFT, UP, DOWN, UP, DOWN. Release.
Double Damage toggle ... hold R-SHIFT, input UP, DOWN, UP, DOWN, LEFT, RIGHT, LEFT, RIGHT. Release.
5000 gold and extras ... hold R-SHIFT, input UP, UP, DOWN, DOWN, LEFT, RIGHT, LEFT, RIGHT. Release.