How to use Multi-Input VST Effect Plug-ins like reagate

Hi y’all

The Context:
I’ve been spending some time recently to find good free gate and vocoder effect plug-ins. There are a few promising out there for instance reagate (-> http://www.kvraudio.com/get/2669.html).
This reagate is an good example for a multi-input effect plug-in, in that it allows you to switch from “main” to “auxiliary” input for the gate control signal. This auxiliary input is like equivalent to cubase side-chain input I guess (see the cubase gate).

The Problem:
But I have not been able to connect anything to this auxiliary input, because it doesn’t show up as for instance the send effects or the activated side-chains do. Btw do I have to say it’s Cubase 6.0.2?

My Question:
Can anyone help me, probably it’s just rtfm (in that case just point me to the right page in the manual) or probably I’d better use real cubase-enabled/side-chaining vst3 plugins for gate and vocoder (if you could point me to those plug-ins…)

Thanx in advance + Cheers
Peter