I can’t find in Halion 4 the Halion 3 feature “Key Activates sample” button (playing a sample from your keyboard will automatically select it). 
Another problem I have is that with a couple of Scarbee keyboard libraries that I’ve imported in Halion 4, when playing notes of short duration there is a click when releasing the key. When pressing the key during 3 or more seconds the click does not occur.
Any ideas?
Many thanks
For the first part of your question, go to the midi mapping tab and in the top right row of icons enable the first square icon ‘enable midi mapping selection options’ and two to the right beside that, the midi din icon, click and enable ‘select zones via midi’.
Thank you very much for your prompt and clear answer 
. It’s perfect. Even with your description I’ve been able to find the answer in the Operations Manual.
Now I can only need to figure out why the click occurs. It is as if it needed a fade out in the release.
If that is the case, you can change the release of the amp envelope in the zone section of the selected sample. I assume something didnt translate properly envelope wise when converting your preset into the Halion 4 VST preset format. Annoying, but not a huge deal to change the release of the samples in question when it comes time to use them.
Thank you again Cantankerous.
I’ve compared the envelopes in Halion 3 and 4 and they are identical. Both are rectangular so the release time is zero in both. Nevertheless in Halion 3 there are no clicks.
I’m traveling until next Tuesday so I can not make tests but I remember having tried for hours with different release times.