1.
Q: Why can not my webcam be used after updating?
A: It is because of api-ms-win-downlevel-shlwapi-l1-1-0.dll missing.
For win7: needing update this package
https://www.microsoft.com/en-nz/download/details.aspx?id=36805
For win10: update to last version.
2.
Q: Why the avatar's gaze going to upside or downside when irises tracking?
A: For now with irises sync, the webcam position must be right on front face. This problem will be fixed on furture.
3.
Q: How to start hands sync?
A: Once you select the target color of hands tracking, the sync should be starting.