This program goes to sleep even if inputs are being made. Perhaps the calculator just doesn't recognize det(73 as an input? If so, I think I might have a solution. I'll test it now.
EDIT: Didn't work

Haha, that's kind of funny. I never thought of it before, but since I scan the keypad registers manually in det(73, then I guess maybe the OS never recognizes keys being pressed. You might just have to disable APD to prevent that from happening. I guess there's also the possiblity that it's just the already known APD bug the OS has from time to time as well, in which case disabling APD is still the solution.

Thanks! There's a hex code that disables APD, right?

Yes, it should be listed in here.

I couldn't upload the program last night, so I've been working on it during my time stuck here at school. It now saves stats for each number of colors (4-11) for accuracy. The statistics it saves are:
▪Best time
▪Fewest guesses
▪Average time
▪Average guesses
▪Games completed
▪Games won
▪Win percentage
▪Games quit
You can reset the stats by holding [clear] for about 3 seconds.

Uploading the program now!

TheBlueKid requested the option to toggle between repetitive and non-repetitive color codes. The scoring system currently in the program works perfectly as is, but it wouldn't work if the color code had redundant numbers. I updated it to use a slightly modified version of my scoring system from W0RDLE, so the scoring is no longer an issue. However, I'll have to figure out how best to integrate that option in the menu before I can upload it.
Download Mastermind CE here

By the way, I tested the APD-disabling hex code and it affected the Wait command, so I won't be including it in future versions.

Yeah, unfortunately the Wait command uses the APD timer to work.