I agree the other instruments sound good, i hope you can get the clarinet behaving well, this is a beautiful piece.
Have you tried putting in the kontakt player's reverb on individual instruments, or the kontakt player's eq on individual instruments?
You'll have to excuse the quality of the red arrows and text i drew, i used the trackpad which doesn't work as well as a mouse.
First you click here on the outputs button to make the outputs appear:
then you click on the instrument's player, and when it is selected the yellow outline appears, kinda hard to see here because the player is orange
Then you can press the little arrow on any one the four empty slots on the outputs marked st1 and st2 (or the surround outputs if you have surround),
and the dropdown menu has reverb and other effects, delays, etc.
also has "filters" on the bottom one which opens yet another dropdown menu of filters and eq's. See pic below.
If i understand correctly what it does, this places the reverb or whatever effect you click, onto all the instruments in this instance of kontakt player...
and to get it onto only one instrument, you select the instrument, make sure it highlighted with yellow line around it, then click the tiny 'Aux' button on the far right of that instruments' player...
then load the effect, reverb or eq, or a combination of them from one of the aux outputs rather than the st1 or st2.
Right above aux 3 and 4, there is a button "edit effect" which will bring up a contol panel for whatever effect is selected. You select the one to edit by highlighting the same aux output button that had the arrow for the dropdown menu.
Hope this helps, i haven't done a lot of changing the sound of the instruments with eq, but i think others here have been using that to get just the right voice from their instruments. I have tried the reverb on individual instruments and like the effect of that, by giving them differents settings, like giving brass a little more than what the strings and woodwinds have.
At the time i did that, i didn't yet know about the aux outputs ( or didn't know what they were for) so i just loaded thoses instruments in different instances of the player.
When I was teaching kids, the struggle was to approach music so that they could understand and learn. To find their learning style.
Late in my career I learned about specific learning styles.
1. oral based; they can learn by listening-3% of the population.
2. visual--need to see, i.e. charts, diagrams, etc-much larger population.
3. kinesthetic-need to act; move; manipulate-100% of students who fail/dropout.
One joke about learning styles is:
If a test is being given by tape recorder, visual learners will look at the recorder.
I am a visual learner.