Just downloaded. I have the same problem. My lines look ‘Pixelated’ with all 3 pen tools, and if I try to erase, the erasers have the same effect. when I hit crtl z, I get a bunch of random squares. I tried uninstalling and reinstalling, but it didn’t fix it.
I’m on Windows 10 on a gateway computer.
Do you need any more info?
Thanks!