I got linking to Tasks to work! Try this:
1. If you have an open Action Memo, save it (one time only).
2. Go to Application Manager
..- Find S Note
..- Force Stop
..- Scroll down to Permissions and allow Calendar
The message "Screen overlay detected...." was due to trying to change S Note's permissions while having an open Action Memo. When there is no open memo,
before turning that permission on, that won't be an issue. Subsequent Action Memo links to Tasks work fine.
(Thank you to user Trel on XDA -
Trel - Senior Member - XDA Forums)