Direct Input is a DirectX module associated with joysticks, mice, and the like. The mod doesn't alter anything related to that at all.

You might try this: select the default controls setup using 1.16.0 and save it (no custom joystick selections, just the standard keyboard controls).
It might be a good idea to unplug the joystick too, just for the next test.
Try test10.exe with that setup and see if it launches properly using just the keyboard, then let us know how that goes.