Okay, here we go:
The script is rather trivial, the difficult part is tricking Apple’s security system. So first create a plain ASCII text file and open that in a text editor (Apple’s built-in TextEdit.app is not good, as it uses formatting. E.g. Atom.app is free to download, if you have nothing else.)
Into that text file you copy and paste following lines:
#!/bin/zsh
outfile=vst3ignorelist.xml
echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<pluginpaths>" >> $outfile
(find -E "/Library/Audio/Plug-Ins/VST3" -type d -regex "(.)+(vst3$)") | while read line
do
echo "<path>"${line}"</path>" >> $outfile
done
echo "</pluginpaths>" >> $outfile
Then save the file to your Desktop under the name CreateVST3IgnoreList.sh
Next open a Terminal window (do a spotlight search for Terminal.app)
Into the Terminal window type
cd Desktop
and hit the return/enter key. Then the command
chmod 777 ./CreateVST3IgnoreList.sh
and again return/enter. Now you should be able to run the script with
./CreateVST3IgnoreList.sh
and hitting return/enter as usual. By now you should have the file vst3ignorelist.xml on your Desktop as well. Next step is to open that file in your plain text editor from before. Since this is the ignore list, you need to delete now all the lines for the plug-ins that you want Dorico to “see”. Right?
Then save the file and the last step is to move it to /Users/whoever/Library/Preferences/Dorico 6 AudioEngine/Dorico 6 AudioEngine VST3 Cache (arm64)
where you change ‘whoever’ to your user name on your Mac. That’s it, start Dorico again and see how it goes.
Don’t hesitate to ask in case of question.