I don’t think I’m wrong in believing that VSL and Steinberg are and/or have been in communication (as one would expect) re expression maps etc.
And that - as you say - quite a lot works already - again, as one would expect… I’ve certainly had some success.
I may have seen a suggestion somewhere that importing Cubase Expression Maps might also work; or at least be a good place to start experimenting - depending on how ambitious one’s project is.
That’s why I suggested optimism as well as incompleteness (there is work to be done) 
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