Hi rlaine,

You will need to modify your above patch slightly.  You should use:

input > ampmod

sidechain > envelope in

envelope out > ampmod mod

ampmod > output

Then set the settings on the ampmod and envelope such that you get the desired effect.

You can easily test if the sidechain input is working by connecting sidechain directly to the output and seeing if the audio from the sidechain buss now comes out the output.

Dan