SPITFIRE DISCOVER and more...

I purchased BBC Discover by Spitfire Audio that comes out with its own application panel It is the first time I try to use external VST libraries with Dorico. I followed step by step the actions indicated by Anthony Hughes in one of his YOUTUBE tutorials. First track, first sound everything ok. As I load a sound in a second track although I assign a different midi channel, the first track sounds as the second. Adding more tracks it goes on like this. I know it sound childish but I don’t understand if there is a step to do I don’t get in Dorico or in the Spitfire App.
Also, I have another issue concerning Kontakt 6. Dorico does not read it in the available VST instrument list. Logic X does.
I have seen there are thing about this on the forum (not really up to date actually) but I’ll check them later because the issue seems to be a bit complicated.
I bought the Discover library because I need to complete a project in Dorico with a minimum of good sounds as soon as possible, but now I am at stake.
I am going to move to Cubase after this project is over.
I attach a report of a file which follows Anthony Hughes instructions step by step.
Thanks Anthony for your beautiful tutorials.
Dorico Diagnostics.zip (547 KB)

I’ve not used BBCSO Discover myself, but I believe you will need one instance of the ‘BBC Symphony Orchestra’ plug-in for each instrument; I don’t think it is a multi-timbral plug-in. So having instantiated the first instance and loaded the desired sound, you should then add another instance of BBC Symphony Orchestra, and load the right preset in there. You can then manually direct each instrument to the appropriate instance using the track headers in Play mode.

Thanks Daniel,
I am sorry to have bothered you, I should have thought about myself.
Thank you for your time and your kindness.