Put recordings on Youtube or Soundcloud, you can then link to them here.
ADSR's / Envelopes are indeed a crucial part of modular unless all you want are Drones, imagine playing a pianio key and the length of time you hold it down is the Sustain, when you let go it rings out is the Release. Its a way of seperating notes from oneanother.
The same envelope that is used to control the Volume of the note van also control the Filter Cutoff to animate and give life and movement to that note.
At the moment my Rack/s have up to 7 envelope generators from simple Attack/Decay to ADSR's and also an LPG.
Enjoy your spare HP, don't rush to fill every last space, this is not like filling sticker books. Resist the urge to 'complete' your rack, its never complete so just relax.