If you haven’t watched the recent tutorials on advanced techniques in OpenToonz by Debraj Sarkar you are missing out.
He covers a lot very quickly so settle in and hold on!
OpenToonz : Advance Animation & Compositing
OpenToonz : Use of Hook Tool for Foot Placement in Walk Cycle
Opentoonz : Character Rigging : Part 1
OpenToonz : Character Rigging : Part 2
Walk Cycle Part 1 (Frame By Frame Animation)
Walk Cycle Part 2 (Motion Key Frame Animation)
These tutorials assume familiarity with working in OpenToonz.
I learned a lot.