Combining packs with sets/projects?

Ok, I know one of the few shitty things in the OT is that you can´t exchange patterns/banks between sets (is this right so far?)

So how can you, for example, get the nintari-pack and combine it with already existing projects? or with another pack?

the free demo-packs are always in 1 separate set, so they have to stay separated?!.
Of course I can mix all the samples by saving the projects all into one set, but I still don´t have the patterns, scenes, parts.

How can you do this? If I can´t integrate the packs, there´s no use buying them (you can as well get a sample library).

Greetings
Andajazz