I’ve had this issue for a while and if you have the same problem where the drawing skips when painting or when moving the canvas with your pen, the issue is related to the latest wacom drivers, I have a 24QHD and the latest drivers that work flawlessly with Paintool Sai are 6.3.42 anything newer will lag when using SAI (despite switching from Wintab to Windows Ink)

Symptoms:

  • Draw a line or move the canvas without lifting the pen
  • The pen will skip randomly after a few seconds
  • Restart and reinstall newer drivers won’t remove the issue
  • Photoshop, CPS, Paintstorm or Tvpaint don’t seem to be affected by this issue
  • Paintool Sai V2 will skip all the time
  • This is using Windows 10 x64

Solution: