The standard way to do this is to use a separate track for each drum, so you can tweak each one to your specific needs, whether that be to use reverb, EQ or whatever.
This Steinberg forum thread indicates how to load SD as a rack, rather than a single plug-in:
Just press F11 which brings up the rack (or Devices/VST Instruments via the dropdown menus). Click on an empty slot in the rack and load Superior Drummer.
Having it in a track also allows you to automate control of settings over time, as you mentioned in your other question.
After you import superior drummer, and at the vst instruments window, click on the icon that looks like an arrow located left of the VST name ('superior drummer' in our case) and select 'activate all outputs'.
Then go to the Superior Drummer mixer and send every output that corresponds to the snare to another output (out 2 for example). To find which outputs I need to send I 'solo' the snare. Then you can add reverb as an insert for that channel only.