Still a bit of a hassle comparing to usual ways, but at least its possible.Browse parameters but scroll down past the published parameters to the MIDI cc's. Right click to automate these directly. You might have to MIDI learn the corresponding controls in the Sampletank UI.
Or try loading a MIDI Out channel, load its Basic preset,, which has some MIDI cc's pre assigned. Set it to an output port number. In the wrapping settings of Sampletank set that as the input port number.
Tweak controls on the MIDI Out channel. Controls are either pre assigned to MIDI cc's or again you have to learn them on the Sampletank UI.
Btw i must give compliments to ST3 resample engine, its really great sounding.
Anyhow, i must say i was quite missing some "proper" EDM/Trance/Hardstyle type of supersaw patches in the default library so here i made for the guys who sometimes use such sound:
https://copy.com/x0gBEaYya6lJfoHa in here you will find 2 leads made using Virus Ti & Dune 2, aswel a multi patch.
And here is a quick demo how the lead sounds in action:
https://copy.com/ROlA31dqnfgxD3Mr