Roman's Layout

There are four layers:

BASE is Norman layout.
SYMB for numbers and symbols.
PLVR is optimized for Plover.
ARRW for navigation (same fingers for arrows as IJKL on QWERTY).

Looking for HJKL arrows? Here we go.

Switching

Tap SYMB to toggle SYMB.
Tap ARRW to toggle ARRW.
Hold SYMB (or ARRW) to activate SYMB (or ARRW) while holding.
Tap PLVR to toggle PLVR.

LEDs

Red: SYMB is on.
Green: PLVR is on.
Blue: ARRW is on.

Functional Keys

Tap F1 to mute microphone via Shush.
Tap F2 to copy screenshot to the clipboard.
Hold SHIFT and tap F2 to save screenshot as a file.
Tap F3, F4, F5, F6 to resize a window via Divvy.
Tap F14, F15 to adjust display brightness.

IMPORTANT: If you have another keyboard connected via Bluetooth, then F14 and F15 will not work. Turn off that Bluetooth keyboard. Re-plug you ErgoDox. Enjoy!

CTRL/ESC

Both of those keys are frequently used in Vim.

Tap CTRL/ESC to send ESC.
Hold CTRL/ESC to use as CTRL.

Activate N-rollover

While in BASE hold left SHIFT and right SHIRT and then tap N.
Then you can activate PLVR and use ErgoDox EZ for steno.