First off, really great job for such a early version of the game!
Here are my results testing on real hardware:
The game does not work on a UnoCart? I just get a black screen on a 4 switch and a jr.
On a harmony cart on my 4 switch all is well, no issues
On a harmony cart on my 2600jr. it loads to title screen, 1 and 3 game select are switching back on forth on their own, try to start game, 1 and 3 are overlaid on top of one another, death comes and pushes the number off screen, then just black screen.