The plugin has an effect only on the selected part (typically with the 'blue rectangle', but also works with individual selections) of the score. Of course, it is also possible to select it everything, it depends on how the dynamic indications are arranged: if the indications are present only in a staff (typically the higher one) or in all the staves but are perfectly coinciding (i.e. dynamic indication equal in the same rhythmic position) can be easily selected the entire score; Otherwise, if each staff (or group of staves) has different dynamic indications, it will be necessary to select one staff at a time and activate the plugin for each selected staff.
The plugin effect only starting from the first dynamic sign it finds; After the last dynamic sign, the Velocity setting is extended until the last measure: if you don't want this you need to make a partial selection of the score.
The plugin considers only the dynamic indications such as 'p', 'f', etc. (not the accents, not the 'crescendo' and 'decrescendo', moreover also absent in the piano-roll); He also considers the 'particular' indications of dynamics, such as the 'sforzato', which as a default setting assigns a certain dynamic to the rhythmic position in which it is located, then decreasing it in the following rhythmic moment. If you don't want this, just assign another dynamic indication immediately after the 'sforzato' (or similar indication), or change the settings of the dynamic sign in Musescore.
The plugin also offers two additional functions:
1) a checkbox that allows you to keep the Velocity settings already assigned to certain notes; Activating this box only makes sense if all the other notes have no velocity setting, otherwise the plugin will not make any change;
2) A button to reset the Velocity setting for all the notes included in a selection (even not to 'Blue Rectangle').
If the score is of considerable size, the processing times can be relatively long.