This article applies to this model FaderPort:
There is a community driven effort on the Reaper forums that provides support for FaderPort in Reaper. Find out more information here.
If you have further questions about the FaderPort Series with Reaper, please know that Reaper community developed their own Native device profile for the Faderport Classic. PreSonus Technical Support is unable to assist with such inquiries as PreSonus does not develop the profile.
Other questions can be posted directly to the Reaper community forum for assistance.