There’s no control for the rounding method used, beyond setting the number of display places on an Answer Measure or setting the Weighting Decimal Places (project properties).
As a side note, something to be aware of is that AWARD® will always be using the full calculated number under the hood, so when moving from, say, one to zero display places it’s possible to see a value go from 10.5 to 10, which looks wrong as intuitively you’d expect this to be rounded up to 11; what will be happening behind the scenes in this situation is that the score is in the range [10.45, 10.5) which is rounded up to 10.5 when rounded to one decimal place, but because the actual number is strictly less than 10.5 it gets rounded to 10 if displayed at zero decimal places.