Well, no one answered my question, so I thought I'd find the answer myself and put the answer on the site... so here goes...
(From the FL Studio Help)
FL Studio supports VSTi plugins with multiple outputs. In the plug-in window, click the down-arrow menu (upper left corner under the red plug-in icon). If the plugin supports multiple output, you will see "enable multiple outputs", select it. Now the first output will be set to whatever FX channel is initially assigned to that plug-in, and each successive FX track will contain the additional outs. For example, a plugin with 4 outputs assigned to FX track 10, takes tracks 10, 11, 12 and 13.
Now I can use those sound banks like I want to!