When starting EnSight (ensight or ensight_server), you can use the command line option -readerdbg to echo user defined reader loading status. This will allow you to see what readers are actually being loaded.

Set the environment variable ENSIGHT20_READER (or legacy ENSIGHT10_READER) to point to the path where additional user defined readers exist and then start up with the -readerdbg option described above to verify that you are loading the reader(s) of interest.