dosbox does not allow you to use the number pad to select the type of game 1-5. Instead of trying to configure the keyboard layout you can conversely press the numlock key 4 times and can now use the numbers. Down side is that you need to press the numlock each time dosbox opened.

Numlock key switch the numeric keypad to work as numbers. Press it just once to switch to numbers.
I don't see any difference when I press it 4 times.
However I noticed it can stuck or work in oposite way for DOSBox when pressed outside DOSBox while DOSBox is running.
"type of game 1-5" is selectable from DOS-Box pre-game setup, it's not part of the game.
This option(s) can be set with regular numeric keys (above letters).
For configure in game keys use CKB - Carma Key Binder tool.

Did I miss something? Why do you need to use numeric keypad as numbers?