Hi again Katherine,
I just did a few quick Google searches. It seems this problem is not necessarily Animation Paper related. Can you try disabling Windows Ink? From what I can read, this should fix the problem for you. You disable it from your Windows system settings.
How many drawbacks – if any – this introduces, I don’t know. Maybe you can just try it and see how well it works for you? Please let me know.
Thanks,
Niels