How to score for double bass and have the pitch come out correctly?

Please excuse if for any reason this has been covered satisfactorily before. This may also need to be posted in the "soundfont" section. I used Polyphony (software) to create an SF2 soundfont for pizzicato double bass with each note (from E1 to C5 played on the appropriate string and assigned to the piano key that has the same pitch. Each WAV file sounds great and has the correct pitch of the corresponding piano key. Then, in MuseScore, I point to my soundfont and it works in that it does indeed play my sounds that I recorded. I try to score. I choose a standard bass clef. I choose concert tuning so that the notes I place on the staff (including many ledger lines as necessary) should match the key assignments in my soundfont and thus play the desired WAV file. Sounds logical, right? But it doesn't work. It gives the correct pitch, but it does not select the desired WAV file. Anyone like to critique my method and contribute any improvements/corrections? I tried turning off concert tuning and setting staff properties to transpose down an octave. This REALLY messes up my soundfont's selection of which WAV file to select. I also tried using the 8vb clef and it does not give the correct pitch and thus does not select the desire WAV file. Thanks for reading.