It works on ReaJS by Cockos.
Place them as follows.
C:\Users\<someone>\AppData\Roaming\REAPER\Effects\0eq00\velocity_mapper
C:\Users\<someone>\AppData\Roaming\REAPER\Data\0eq00\Default.txt
C:\Users\<someone>\AppData\Roaming\REAPER\Data\0eq00\MODARTT Pianoteq.txt
C:\Users\<someone>\AppData\Roaming\REAPER\Data\0eq00\SalamanderStrikesBack.txt
...