HALion sounds not assigned to instrumental parts

Thank you both for your prompt replies. Yes, I have downloaded all three - and reinstalled them all several times. The Symphonic Sounds seem to work fine on the pre-installed demo. projects. I can also use some of Symphonic Sounds but not find the full range. (see screenshot). I assume in any case that they would automatically assign themselves to the various instrumental parts. I am also curious that the default playback template is always Sonic. Is that to be expected? My feeling, after gone through many of the fixes with technical support, but to no avail, that there is something fundamentally awry, though quite what and where is beyond me. I would also add that on several occasions since it was installed, Dorico has frozen and had to be removed by Forced Quit. Any further help is very welcome. Thanks.