If I click on a note and slide it up or down the stave the correct pitch plays, but when I release that note, irrespective of the position, it plays the SAME PITCH that is at least an octave below that position. My SETUP entails one player with 4 instruments consisting of 3 treble clefs and 2 bass clefs. All instruments are channeled to Halion Sonic. I have deleted everything to no avail. Would someone please advise as to how to overcome this issue. Thanks.
John, your description is a little vague, what are the instruments exactly and why do you have 5 clefs for 4 instruments? Can you post a part of the project?
Mean’t to say 5 instruments consisting of 5 pianos which in turn is channeled to Halion. The reason for 5 is to separate them into SATB with an additional bass clef otherwise unable to mute them separately, when wish to do so. I desire to hear either one instrument with another or two with another…etc. how do I upload project?
The clef in question is the H:Alto clef.
Song 1.dorico (1.2 MB). To clarify: If I press to play a G3 it sounds somewhere in the range below, but not a G2, If I press to play a D3 it sounds somewhere in the range below, but not a D2…etc. The pitch that sounds in the range below is the exact same pitch for any pitch I play above. Thanks.
For some reason you have assigned a Percussion Map to this part…
Also, I would use the Transpose Down 1 Octave Expression Map for the Tenor.
Thanks John for posting your example file. 
In Write Mode I notice that the Oboe (bottom system) plays two octaves higher. You have configured that staff with Expression map HSSE Acoustic Bass VX, which might explain it.
If in Write Mode I put music into the empty Alto staff, every note plays back with a low c. This has already been explained by Janus (just above).
If you - in Play Mode - click on the little cogwheel and open the Endpoint Setup configuration, you can reset these two instances to default:
After this you will probably want to put the oboe staff into an audible range (by shifting it up two octaves and giving it a treble clef).
Thanks KB and Janus. I’ll try that.