I am actually doing it in Cpp, with the same results that you have. As far as I investigated engine code, we will have to rewrite couple of functions responsible for player input and physical stuff applied to Pawn. I would like to find other solution, cause I am pretty sure that guys from Epic did not just forget to finish the AddMovementInput(), and there is something else that we don’t understand. Or it will be fixed soon, at least.
Let me clarify things a little. Here is the member function of the custom character class, which is inherited from ACharacter (child of Pawn). It is a standard func for a first person cpp template
The thing which actually applies an input to the Pawn’s position is AddMovementInput(). Here is it’s definition:
It accepts direction and magnitude. However, the magnitude does not have any effect, except for a negative/positive value, which change the direction. Thus, I can only let pawn move into direction with some constant speed, not faster, not slower.