You can use the Interpret function-> to modify the velocities and timings of notes according to any written or indicated dynamics found. The selection of interpretations available is as follows:
Sets a velocity to each note based on the last piece of text of "Dynamic" type seen on the same staff (only texts of the form pp, p, mp, mf, f, ff, fff, etc., are matched; these are the texts that are available by default when entering text events of this style).
Makes the notes gradually increase or decrease in velocity during a crescendo or decrescendo hairpin.
Makes notes that land on bar or beat boundaries slightly louder (greater velocity) than the surrounding notes.
Shortens unslurred notes, shortens staccato notes more, and gives notes inside slurs and tenuto notes their full length.