@MesaSean
It's really not that difficult.
I've found the Ground Control Pro to be the easiest Midi device to program of all my Midi devices..
The Helix is more complicated.
My Midi Setup: GCP Midi Out > Midi Cable > HX Stomp XL Midi In / HX Stomp XL Midi Out/Thru > Midi Cable > Diezel VHX Midi In
To set the VHX FX to Toggle on/Off with the GCP:
1. Press both Setup Buttons on GCP to enter Setup Mode
2. Press "Instant Access" button
3. Press "Yes" button until display reads: CH01 CTL004 (this means Button #1 will use Midi Channel 1 to control #004
4. Press "Cursor" right button to move to Control #
5. Press "No/Yes" buttons to set Control # to #017 (this Toggles the VHX Pre-Loop on and off)
6. Use "Bank Up/Down" buttons to move through, and set each of the 8 Instant Access buttons to toggle FX
7. For instance: I set Instant Access button #2 to Control #019 to Toggle on and off VHX FX Block - FX 2 (I usually set to Phaser/Chorus)
8. I set IA buttons #3 & #4 to Control #020 & #021 to Toggle on and off VHX FX Block - FX 3 & FX4 (Delay & Reverb)
9. I set IA button #8 to Control #006 to Toggle on/off the VHX Boost function (+3db boost)
Since I use the Hx Stomp XL in the Pre-Loop:
10. I set GCP Instant Access button #5 to Control #050 (Toggles on/off HX Button #1 - Usually a Drive Pedal
11. I set GCP Instant Access button #6 to Control #051 (Toggles on/off HX Button #2 - Usually a Pitch Shift)
12. I set GCP Instant Access button #7 to Control #052 (Toggles on/off HX Button #3 - Usually a Mod: Chorus/Phaser, etc..
When you are done programming all 8 Instant Access buttons, Press "Edit" button, then Press "Yes" button to save.
You're all set up!
*make sure your VHX is set to Midi Omni, and your Helix to Midi Ch 1