Hi Paul
Can you get the dynamics to work at all? And if so, are you using the velocity x-fade settings as recommended on page 30 of the "Optimising Sibelius" PDF? - i.e. Vel.XF assigned to controller 11? I've created a totally new score with a single oboe, 5 notes going from ppp to ff, VSL House Style, one Synchron Player device in the playback config, loaded with the standard Oboe (French) factory preset, but with the Vel.XF controller changed to 11 and Expression changed to 12.
This is exactly as per the VI settings, and excalty as per the instructions in the "OPtimising Sibelius" PDF, as far as I can work out.
But it plays back with all notes on a constant volume!
Oddly, if I leave the VelXF controller at the default (2) and expression at 11, then it seems to work ... but in that case why are VSL telling us to make that change?