Can you make a MIDI Envelope using Simple Instrument Tracks?

Hello,

I was just wondering, is it possible to draw a MIDI envelope using simple instrument tracks?  I only see Audio Envelopes available, only when I seperate them do I see the midi controls in the filter.   Is there something I am missing?

If not, I don't get why Cakewalk doesn't show ALL options if the track is a MIDI AND Audio Track.

Thank You,
Adam